256312555 has 4 divisors (see below), whose sum is σ = 307575072. Its totient is φ = 205050040.

The previous prime is 256312547. The next prime is 256312561. The reversal of 256312555 is 555213652.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 256312555 - 2³ = 256312547 is a prime.

It is a super-2 number, since 2×256312555² = 131392251701256050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256312555.

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, 25631251 + ... + 25631260.

It is an arithmetic number, because the mean of its divisors is an integer number (76893768).

Almost surely, 2^256312555 is an apocalyptic number.

256312555 is a deficient number, since it is larger than the sum of its proper divisors (51262517).

256312555 is an equidigital number, since it uses as much as digits as its factorization.

256312555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51262516.

The product of its digits is 45000, while the sum is 34.

The square root of 256312555 is about 16009.7643642872. The cubic root of 256312555 is about 635.2187272212.

The spelling of 256312555 in words is "two hundred fifty-six million, three hundred twelve thousand, five hundred fifty-five".