256511032457 has 2 divisors, whose sum is σ = 256511032458. Its totient is φ = 256511032456.

The previous prime is 256511032441. The next prime is 256511032513. The reversal of 256511032457 is 754230115652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220130810761 + 36380221696 = 469181^2 + 190736^2 .

It is a cyclic number.

It is not a de Polignac number, because 256511032457 - 2⁴ = 256511032441 is a prime.

It is a super-2 number, since 2×256511032457² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (256511035457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128255516228 + 128255516229.

It is an arithmetic number, because the mean of its divisors is an integer number (128255516229).

Almost surely, 2^256511032457 is an apocalyptic number.

It is an amenable number.

256511032457 is a deficient number, since it is larger than the sum of its proper divisors (1).

256511032457 is an equidigital number, since it uses as much as digits as its factorization.

256511032457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252000, while the sum is 41.

The spelling of 256511032457 in words is "two hundred fifty-six billion, five hundred eleven million, thirty-two thousand, four hundred fifty-seven".