649988720 has 40 divisors (see below), whose sum is σ = 1517018976. Its totient is φ = 258998528.

The previous prime is 649988701. The next prime is 649988737. The reversal of 649988720 is 27889946.

649988720 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×649988720² = 844970672254476800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5594 + ... + 36486.

Almost surely, 2^649988720 is an apocalyptic number.

It is an amenable number.

649988720 is an abundant number, since it is smaller than the sum of its proper divisors (867030256).

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

649988720 is a wasteful number, since it uses less digits than its factorization.

649988720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31169 (or 31163 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 53.

The square root of 649988720 is about 25494.8763480037. The cubic root of 649988720 is about 866.2340944519.

The spelling of 649988720 in words is "six hundred forty-nine million, nine hundred eighty-eight thousand, seven hundred twenty".