656221957775 has 12 divisors (see below), whose sum is σ = 813725301432. Its totient is φ = 524971067040.

The previous prime is 656221957771. The next prime is 656221957841. The reversal of 656221957775 is 577759122656.

656221957775 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 656221957775 - 2² = 656221957771 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656221957771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3667544 + ... + 3842306.

It is an arithmetic number, because the mean of its divisors is an integer number (67810441786).

Almost surely, 2^656221957775 is an apocalyptic number.

656221957775 is a deficient number, since it is larger than the sum of its proper divisors (157503343657).

656221957775 is a wasteful number, since it uses less digits than its factorization.

656221957775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324970 (or 324965 counting only the distinct ones).

The product of its digits is 55566000, while the sum is 62.

The spelling of 656221957775 in words is "six hundred fifty-six billion, two hundred twenty-one million, nine hundred fifty-seven thousand, seven hundred seventy-five".