646977492 has 36 divisors (see below), whose sum is σ = 1869046816. Its totient is φ = 184850640.

The previous prime is 646977479. The next prime is 646977509. The reversal of 646977492 is 294779646.

It is a happy number.

646977492 is a `hidden beast` number, since 64 + 6 + 97 + 7 + 492 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×646977492² = 837159750309220128, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 1283434 + ... + 1283937.

Almost surely, 2^646977492 is an apocalyptic number.

It is an amenable number.

646977492 is an abundant number, since it is smaller than the sum of its proper divisors (1222069324).

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

646977492 is a wasteful number, since it uses less digits than its factorization.

646977492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2567388 (or 2567383 counting only the distinct ones).

The product of its digits is 4572288, while the sum is 54.

The square root of 646977492 is about 25435.7522397117. The cubic root of 646977492 is about 864.8943446303.

The spelling of 646977492 in words is "six hundred forty-six million, nine hundred seventy-seven thousand, four hundred ninety-two".