646640448 has 28 divisors (see below), whose sum is σ = 1710903360. Its totient is φ = 215546752.

The previous prime is 646640431. The next prime is 646640503. The reversal of 646640448 is 844046646.

It is a happy number.

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 3 ways as a sum of consecutive naturals, for example, 1683768 + ... + 1684151.

Almost surely, 2^646640448 is an apocalyptic number.

It is an amenable number.

646640448 is an abundant number, since it is smaller than the sum of its proper divisors (1064262912).

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

646640448 is a wasteful number, since it uses less digits than its factorization.

646640448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3367934 (or 3367924 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 42.

The square root of 646640448 is about 25429.1259779018. The cubic root of 646640448 is about 864.7441291601.

The spelling of 646640448 in words is "six hundred forty-six million, six hundred forty thousand, four hundred forty-eight".