1256170542457 has 2 divisors, whose sum is σ = 1256170542458. Its totient is φ = 1256170542456.

The previous prime is 1256170542409. The next prime is 1256170542461. The reversal of 1256170542457 is 7542450716521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 954237876201 + 301932666256 = 976851^2 + 549484^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1256170542457 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1256170542457.

It is not a weakly prime, because it can be changed into another prime (1256177542457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628085271228 + 628085271229.

It is an arithmetic number, because the mean of its divisors is an integer number (628085271229).

Almost surely, 2^{1256170542457} is an apocalyptic number.

It is an amenable number.

1256170542457 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256170542457 is an equidigital number, since it uses as much as digits as its factorization.

1256170542457 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2352000, while the sum is 49.

The spelling of 1256170542457 in words is "one trillion, two hundred fifty-six billion, one hundred seventy million, five hundred forty-two thousand, four hundred fifty-seven".