256734140733557 has 8 divisors (see below), whose sum is σ = 270301876466400. Its totient is φ = 243171946254384.

The previous prime is 256734140733517. The next prime is 256734140733569. The reversal of 256734140733557 is 755337041437652.

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 256734140733557 - 2³⁶ = 256665421256821 is a prime.

It is a super-2 number, since 2×256734140733557² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256734140733557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256734140733517) 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, 1385218307 + ... + 1385403632.

It is an arithmetic number, because the mean of its divisors is an integer number (33787734558300).

Almost surely, 2^{256734140733557} is an apocalyptic number.

It is an amenable number.

256734140733557 is a deficient number, since it is larger than the sum of its proper divisors (13567735732843).

256734140733557 is a wasteful number, since it uses less digits than its factorization.

256734140733557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2770626835.

The product of its (nonzero) digits is 222264000, while the sum is 62.

The spelling of 256734140733557 in words is "two hundred fifty-six trillion, seven hundred thirty-four billion, one hundred forty million, seven hundred thirty-three thousand, five hundred fifty-seven".