1256938457 has 2 divisors, whose sum is σ = 1256938458. Its totient is φ = 1256938456.

The previous prime is 1256938453. The next prime is 1256938481. The reversal of 1256938457 is 7548396521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 823632601 + 433305856 = 28699^2 + 20816^2 .

It is a cyclic number.

It is not a de Polignac number, because 1256938457 - 2² = 1256938453 is a prime.

It is not a weakly prime, because it can be changed into another prime (1256938453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628469228 + 628469229.

It is an arithmetic number, because the mean of its divisors is an integer number (628469229).

Almost surely, 2^1256938457 is an apocalyptic number.

It is an amenable number.

1256938457 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256938457 is an equidigital number, since it uses as much as digits as its factorization.

1256938457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1814400, while the sum is 50.

The square root of 1256938457 is about 35453.3278691860. The cubic root of 1256938457 is about 1079.2067955469.

The spelling of 1256938457 in words is "one billion, two hundred fifty-six million, nine hundred thirty-eight thousand, four hundred fifty-seven".