257156856004321 has 27 divisors (see below), whose sum is σ = 323924451984153. Its totient is φ = 203463610590240.

The previous prime is 257156856004297. The next prime is 257156856004333. The reversal of 257156856004321 is 123400658651752.

The square root of 257156856004321 is 16036111.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 41447007064225 + 215709848940096 = 6437935^2 + 14687064^2 .

It is not a de Polignac number, because 257156856004321 - 2⁷ = 257156856004193 is a prime.

It is a super-2 number, since 2×257156856004321² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257156856004021) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1459197991 + ... + 1459374211.

It is an arithmetic number, because the mean of its divisors is an integer number (11997201925339).

Almost surely, 2^{257156856004321} is an apocalyptic number.

257156856004321 is the 16036111-st square number.

257156856004321 is the 8018056-th centered octagonal number.

It is an amenable number.

257156856004321 is a deficient number, since it is larger than the sum of its proper divisors (66767595979832).

257156856004321 is an frugal number, since it uses more digits than its factorization.

257156856004321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352482 (or 176241 counting only the distinct ones).

The product of its (nonzero) digits is 12096000, while the sum is 55.

The spelling of 257156856004321 in words is "two hundred fifty-seven trillion, one hundred fifty-six billion, eight hundred fifty-six million, four thousand, three hundred twenty-one".