656999425 has 24 divisors (see below), whose sum is σ = 864259416. Its totient is φ = 493731840.

The previous prime is 656999419. The next prime is 656999443. The reversal of 656999425 is 524999656.

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

It can be written as a sum of positive squares in 12 ways, for example, as 145515969 + 511483456 = 12063^2 + 22616^2 .

It is not a de Polignac number, because 656999425 - 2⁷ = 656999297 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 284877 + ... + 287173.

It is an arithmetic number, because the mean of its divisors is an integer number (36010809).

Almost surely, 2^656999425 is an apocalyptic number.

It is an amenable number.

656999425 is a deficient number, since it is larger than the sum of its proper divisors (207259991).

656999425 is a wasteful number, since it uses less digits than its factorization.

656999425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2997 (or 2992 counting only the distinct ones).

The product of its digits is 5248800, while the sum is 55.

The square root of 656999425 is about 25632.0000195069. Note that the first 4 decimals coincide. The cubic root of 656999425 is about 869.3373317319.

The spelling of 656999425 in words is "six hundred fifty-six million, nine hundred ninety-nine thousand, four hundred twenty-five".