255515631617 has 4 divisors (see below), whose sum is σ = 258386593860. Its totient is φ = 252644669376.

The previous prime is 255515631577. The next prime is 255515631643. The reversal of 255515631617 is 716136515552.

255515631617 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 36604872976 + 218910758641 = 191324^2 + 467879^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-255515631617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (255515631697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1435480988 + ... + 1435481165.

It is an arithmetic number, because the mean of its divisors is an integer number (64596648465).

Almost surely, 2^255515631617 is an apocalyptic number.

It is an amenable number.

255515631617 is a deficient number, since it is larger than the sum of its proper divisors (2870962243).

255515631617 is an equidigital number, since it uses as much as digits as its factorization.

255515631617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2870962242.

The product of its digits is 945000, while the sum is 47.

The spelling of 255515631617 in words is "two hundred fifty-five billion, five hundred fifteen million, six hundred thirty-one thousand, six hundred seventeen".