656590393439 has 4 divisors (see below), whose sum is σ = 663967813680. Its totient is φ = 649212973200.

The previous prime is 656590393429. The next prime is 656590393441. The reversal of 656590393439 is 934393095656.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 656590393439 - 2⁸ = 656590393183 is a prime.

It is a super-2 number, since 2×656590393439² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656590393429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3688709987 + ... + 3688710164.

It is an arithmetic number, because the mean of its divisors is an integer number (165991953420).

Almost surely, 2^656590393439 is an apocalyptic number.

656590393439 is a deficient number, since it is larger than the sum of its proper divisors (7377420241).

656590393439 is an equidigital number, since it uses as much as digits as its factorization.

656590393439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7377420240.

The product of its (nonzero) digits is 70858800, while the sum is 62.

The spelling of 656590393439 in words is "six hundred fifty-six billion, five hundred ninety million, three hundred ninety-three thousand, four hundred thirty-nine".