1256057256857 has 8 divisors (see below), whose sum is σ = 1353355787784. Its totient is φ = 1158855689088.

The previous prime is 1256057256851. The next prime is 1256057256871. The reversal of 1256057256857 is 7586527506521.

It can be written as a sum of positive squares in 4 ways, for example, as 429587174041 + 826470082816 = 655429^2 + 909104^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1256057256857 - 2³⁰ = 1254983515033 is a prime.

It is a super-4 number, since 4×1256057256857⁴ (a number of 49 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1256057256796 and 1256057256805.

It is not an unprimeable number, because it can be changed into a prime (1256057256851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24213878 + ... + 24265695.

It is an arithmetic number, because the mean of its divisors is an integer number (169169473473).

Almost surely, 2^{1256057256857} is an apocalyptic number.

It is an amenable number.

1256057256857 is a deficient number, since it is larger than the sum of its proper divisors (97298530927).

1256057256857 is a wasteful number, since it uses less digits than its factorization.

1256057256857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48481579.

The product of its (nonzero) digits is 35280000, while the sum is 59.

The spelling of 1256057256857 in words is "one trillion, two hundred fifty-six billion, fifty-seven million, two hundred fifty-six thousand, eight hundred fifty-seven".