255615985 has 4 divisors (see below), whose sum is σ = 306739188. Its totient is φ = 204492784.

The previous prime is 255615973. The next prime is 255615991. The reversal of 255615985 is 589516552.

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

It can be written as a sum of positive squares in 2 ways, for example, as 166823056 + 88792929 = 12916^2 + 9423^2 .

It is a cyclic number.

It is not a de Polignac number, because 255615985 - 2⁵ = 255615953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25561594 + ... + 25561603.

It is an arithmetic number, because the mean of its divisors is an integer number (76684797).

Almost surely, 2^255615985 is an apocalyptic number.

It is an amenable number.

255615985 is a deficient number, since it is larger than the sum of its proper divisors (51123203).

255615985 is an equidigital number, since it uses as much as digits as its factorization.

255615985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51123202.

The product of its digits is 540000, while the sum is 46.

The square root of 255615985 is about 15987.9950275199. The cubic root of 255615985 is about 634.6427692904.

The spelling of 255615985 in words is "two hundred fifty-five million, six hundred fifteen thousand, nine hundred eighty-five".