1255421621 has 2 divisors, whose sum is σ = 1255421622. Its totient is φ = 1255421620.

The previous prime is 1255421569. The next prime is 1255421689. The reversal of 1255421621 is 1261245521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1229554225 + 25867396 = 35065^2 + 5086^2 .

It is a cyclic number.

It is not a de Polignac number, because 1255421621 - 2¹⁰ = 1255420597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1255421521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 627710810 + 627710811.

It is an arithmetic number, because the mean of its divisors is an integer number (627710811).

Almost surely, 2^1255421621 is an apocalyptic number.

It is an amenable number.

1255421621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1255421621 is an equidigital number, since it uses as much as digits as its factorization.

1255421621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4800, while the sum is 29.

The square root of 1255421621 is about 35431.9293999071. The cubic root of 1255421621 is about 1078.7725025662.

The spelling of 1255421621 in words is "one billion, two hundred fifty-five million, four hundred twenty-one thousand, six hundred twenty-one".