649761880 has 16 divisors (see below), whose sum is σ = 1461964320. Its totient is φ = 259904736.

The previous prime is 649761841. The next prime is 649761899. The reversal of 649761880 is 88167946.

It is a super-2 number, since 2×649761880² = 844381001402268800, 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 3 ways as a sum of consecutive naturals, for example, 8121984 + ... + 8122063.

It is an arithmetic number, because the mean of its divisors is an integer number (91372770).

Almost surely, 2^649761880 is an apocalyptic number.

It is an amenable number.

649761880 is an abundant number, since it is smaller than the sum of its proper divisors (812202440).

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

649761880 is a wasteful number, since it uses less digits than its factorization.

649761880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16244058 (or 16244054 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 49.

The square root of 649761880 is about 25490.4272227831. The cubic root of 649761880 is about 866.1333135209.

The spelling of 649761880 in words is "six hundred forty-nine million, seven hundred sixty-one thousand, eight hundred eighty".