656320942081 has 4 divisors (see below), whose sum is σ = 750081076672. Its totient is φ = 562560807492.

The previous prime is 656320942073. The next prime is 656320942091. The reversal of 656320942081 is 180249023656.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 656320942081 - 2³ = 656320942073 is a prime.

It is a super-2 number, since 2×656320942081² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656320942091) by changing a digit.

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, 46880067285 + ... + 46880067298.

It is an arithmetic number, because the mean of its divisors is an integer number (187520269168).

Almost surely, 2^656320942081 is an apocalyptic number.

It is an amenable number.

656320942081 is a deficient number, since it is larger than the sum of its proper divisors (93760134591).

656320942081 is an equidigital number, since it uses as much as digits as its factorization.

656320942081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93760134590.

The product of its (nonzero) digits is 622080, while the sum is 46.

The spelling of 656320942081 in words is "six hundred fifty-six billion, three hundred twenty million, nine hundred forty-two thousand, eighty-one".