256718740 has 24 divisors (see below), whose sum is σ = 539532000. Its totient is φ = 102607008.

The previous prime is 256718723. The next prime is 256718767. The reversal of 256718740 is 47817652.

It is a super-2 number, since 2×256718740² = 131809022934375200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 256718693 and 256718702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25699 + ... + 34261.

It is an arithmetic number, because the mean of its divisors is an integer number (22480500).

Almost surely, 2^256718740 is an apocalyptic number.

256718740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256718740 is an abundant number, since it is smaller than the sum of its proper divisors (282813260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256718740 is a wasteful number, since it uses less digits than its factorization.

256718740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10071 (or 10069 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 256718740 is about 16022.4448821021. Note that the first 3 decimals coincide. The cubic root of 256718740 is about 635.5540991965.

The spelling of 256718740 in words is "two hundred fifty-six million, seven hundred eighteen thousand, seven hundred forty".