256642266 has 8 divisors (see below), whose sum is σ = 513284544. Its totient is φ = 85547420.

The previous prime is 256642259. The next prime is 256642301. The reversal of 256642266 is 662246652.

256642266 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

256642266 is an admirable number.

It is a super-2 number, since 2×256642266² = 131730505395229512, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21386850 + ... + 21386861.

It is an arithmetic number, because the mean of its divisors is an integer number (64160568).

Almost surely, 2^256642266 is an apocalyptic number.

256642266 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

256642266 is a wasteful number, since it uses less digits than its factorization.

256642266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42773716.

The product of its digits is 207360, while the sum is 39.

The square root of 256642266 is about 16020.0582395945. The cubic root of 256642266 is about 635.4909844804.

The spelling of 256642266 in words is "two hundred fifty-six million, six hundred forty-two thousand, two hundred sixty-six".