656065640 has 16 divisors (see below), whose sum is σ = 1476147780. Its totient is φ = 262426240.

The previous prime is 656065633. The next prime is 656065643. The reversal of 656065640 is 46560656.

It can be written as a sum of positive squares in 2 ways, for example, as 548777476 + 107288164 = 23426^2 + 10358^2 .

It is a junction number, because it is equal to n+sod(n) for n = 656065594 and 656065603.

It is not an unprimeable number, because it can be changed into a prime (656065643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8200781 + ... + 8200860.

Almost surely, 2^656065640 is an apocalyptic number.

It is an amenable number.

656065640 is an abundant number, since it is smaller than the sum of its proper divisors (820082140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

656065640 is a wasteful number, since it uses less digits than its factorization.

656065640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16401652 (or 16401648 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 656065640 is about 25613.7783233946. The cubic root of 656065640 is about 868.9252770576.

The spelling of 656065640 in words is "six hundred fifty-six million, sixty-five thousand, six hundred forty".