656999423 has 12 divisors (see below), whose sum is σ = 703191888. Its totient is φ = 613630080.

The previous prime is 656999419. The next prime is 656999443. The reversal of 656999423 is 324999656.

It is a Cunningham number, because it is equal to 25632²-1.

It is not a de Polignac number, because 656999423 - 2² = 656999419 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 (656999443) 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 11 ways as a sum of consecutive naturals, for example, 12815 + ... + 38447.

It is an arithmetic number, because the mean of its divisors is an integer number (58599324).

Almost surely, 2^656999423 is an apocalyptic number.

656999423 is a deficient number, since it is larger than the sum of its proper divisors (46192465).

656999423 is a wasteful number, since it uses less digits than its factorization.

656999423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25742 (or 25723 counting only the distinct ones).

The product of its digits is 3149280, while the sum is 53.

The square root of 656999423 is about 25631.9999804931. Note that the first 4 decimals coincide. The cubic root of 656999423 is about 869.3373308498.

The spelling of 656999423 in words is "six hundred fifty-six million, nine hundred ninety-nine thousand, four hundred twenty-three".