256006690 has 8 divisors (see below), whose sum is σ = 460812060. Its totient is φ = 102402672.

The previous prime is 256006687. The next prime is 256006717. The reversal of 256006690 is 96600652.

It can be written as a sum of positive squares in 2 ways, for example, as 249861249 + 6145441 = 15807^2 + 2479^2 .

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

It is a super-2 number, since 2×256006690² = 131078850649512200, 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, 12800325 + ... + 12800344.

Almost surely, 2^256006690 is an apocalyptic number.

256006690 is a deficient number, since it is larger than the sum of its proper divisors (204805370).

256006690 is a wasteful number, since it uses less digits than its factorization.

256006690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25600676.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 256006690 is about 16000.2090611342. The cubic root of 256006690 is about 634.9659518396.

The spelling of 256006690 in words is "two hundred fifty-six million, six thousand, six hundred ninety".