661012318256 has 40 divisors (see below), whose sum is σ = 1290281322960. Its totient is φ = 328037808384.

The previous prime is 661012318243. The next prime is 661012318273. The reversal of 661012318256 is 652813210166.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 8405390 + ... + 8483666.

It is an arithmetic number, because the mean of its divisors is an integer number (32257033074).

Almost surely, 2^661012318256 is an apocalyptic number.

It is an amenable number.

661012318256 is a deficient number, since it is larger than the sum of its proper divisors (629269004704).

661012318256 is a wasteful number, since it uses less digits than its factorization.

661012318256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82221 (or 82215 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 41.

The spelling of 661012318256 in words is "six hundred sixty-one billion, twelve million, three hundred eighteen thousand, two hundred fifty-six".