256520099 has 8 divisors (see below), whose sum is σ = 279975360. Its totient is φ = 233087400.

The previous prime is 256520027. The next prime is 256520107. The reversal of 256520099 is 990025652.

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 256520099 - 2¹² = 256516003 is a prime.

It is a super-2 number, since 2×256520099² = 131605122381939602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256520899) 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, 25772 + ... + 34310.

It is an arithmetic number, because the mean of its divisors is an integer number (34996920).

Almost surely, 2^256520099 is an apocalyptic number.

256520099 is a deficient number, since it is larger than the sum of its proper divisors (23455261).

256520099 is a wasteful number, since it uses less digits than its factorization.

256520099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11281.

The product of its (nonzero) digits is 48600, while the sum is 38.

The square root of 256520099 is about 16016.2448470295. The cubic root of 256520099 is about 635.3901328808.

The spelling of 256520099 in words is "two hundred fifty-six million, five hundred twenty thousand, ninety-nine".