256715715 has 8 divisors (see below), whose sum is σ = 410745168. Its totient is φ = 136915040.

The previous prime is 256715689. The next prime is 256715717. The reversal of 256715715 is 517517652.

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

It is not a de Polignac number, because 256715715 - 2¹³ = 256707523 is a prime.

It is a super-3 number, since 3×256715715³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (256715717) 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, 8557176 + ... + 8557205.

It is an arithmetic number, because the mean of its divisors is an integer number (51343146).

Almost surely, 2^256715715 is an apocalyptic number.

256715715 is a deficient number, since it is larger than the sum of its proper divisors (154029453).

256715715 is a wasteful number, since it uses less digits than its factorization.

256715715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17114389.

The product of its digits is 73500, while the sum is 39.

The square root of 256715715 is about 16022.3504829972. The cubic root of 256715715 is about 635.5516028735.

The spelling of 256715715 in words is "two hundred fifty-six million, seven hundred fifteen thousand, seven hundred fifteen".