656166661656 has 32 divisors (see below), whose sum is σ = 1789545441600. Its totient is φ = 198838382240.

The previous prime is 656166661637. The next prime is 656166661727.

656166661656 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 656166661656.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 1242739626 + ... + 1242740153.

It is an arithmetic number, because the mean of its divisors is an integer number (55923295050).

Almost surely, 2^656166661656 is an apocalyptic number.

656166661656 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

656166661656 is an abundant number, since it is smaller than the sum of its proper divisors (1133378779944).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

656166661656 is a wasteful number, since it uses less digits than its factorization.

656166661656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2485479799 (or 2485479795 counting only the distinct ones).

The product of its digits is 41990400, while the sum is 60.

The spelling of 656166661656 in words is "six hundred fifty-six billion, one hundred sixty-six million, six hundred sixty-one thousand, six hundred fifty-six".