P · Proven prime
Enter a value, an expression, or a term with a variable like 10^n+1 to list a range.
Switch to Database id to look a number up by its stored id.
Reading never stores anything; use Create to add a number to the database.
See the expression syntax & functions reference.
↪
Term #1 of the Home prime · Base 13 sequence of
166
Term #1 of the Home prime · Base 14 sequence of
58
Term #1 of the Aliquot variants · Augmented · σ(n) − n + 1 sequence of
364
Term #1 of the Inverse home prime · Base 18 sequence of
161
Term #1 of the Inverse home prime · Base 22 sequence of
57
Term #1 of the Inverse home prime · Base 24 sequence of
221
Term #1 of the Inverse home prime · Base 32 sequence of
65
Term #1 of the Conway climb · Base 11 sequence of
375
Term #1 of the Conway climb · Base 13 sequence of
166
Term #1 of the Conway climb · Base 14 sequence of
58
Term #3 of the Second-class home prime · Base 3 sequence of
72
Term #2 of the Second-class home prime · Base 8 sequence of
420
Term #2 of the Second-class home prime · Base 10 sequence of
312
Term #2 of the Mid-divisor concatenation · Base 2 sequence of
182
Term #1 of the Mid-divisor concatenation · Base 3 sequence of
240
Term #1 of the Mid-divisor concatenation · Base 8 sequence of
222
Is factor of
Primality
Verified directlyproven prime
Checked deterministically (below 300 digits).
From the command linefdb · curl
fdb
fdb number '421' --detail 2
curl
curl -s 'https://factordb.com:4059/rpc' -H 'Content-Type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"get_number","params":{"target":{"expr":"421"},"decimal":false,"detail":2}}'