646459972 has 12 divisors (see below), whose sum is σ = 1140213760. Its totient is φ = 320684616.

The previous prime is 646459951. The next prime is 646459973. The reversal of 646459972 is 279954646.

It is not an unprimeable number, because it can be changed into a prime (646459973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 635772 + ... + 636787.

Almost surely, 2^646459972 is an apocalyptic number.

It is an amenable number.

646459972 is a deficient number, since it is larger than the sum of its proper divisors (493753788).

646459972 is a wasteful number, since it uses less digits than its factorization.

646459972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1272690 (or 1272688 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 52.

The square root of 646459972 is about 25425.5771222602. The cubic root of 646459972 is about 864.6636722470.

The spelling of 646459972 in words is "six hundred forty-six million, four hundred fifty-nine thousand, nine hundred seventy-two".