646458816 has 28 divisors (see below), whose sum is σ = 1710422792. Its totient is φ = 215486208.

The previous prime is 646458773. The next prime is 646458851. The reversal of 646458816 is 618854646.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1683295 + ... + 1683678.

Almost surely, 2^646458816 is an apocalyptic number.

It is an amenable number.

646458816 is an abundant number, since it is smaller than the sum of its proper divisors (1063963976).

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

646458816 is a wasteful number, since it uses less digits than its factorization.

646458816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3366988 (or 3366978 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 48.

The square root of 646458816 is about 25425.5543892360. The cubic root of 646458816 is about 864.6631568494.

The spelling of 646458816 in words is "six hundred forty-six million, four hundred fifty-eight thousand, eight hundred sixteen".