649073664 has 66 divisors (see below), whose sum is σ = 1874212730. Its totient is φ = 216354816.

The previous prime is 649073627. The next prime is 649073671. The reversal of 649073664 is 466370946.

It can be written as a sum of positive squares in only one way, i.e., 553190400 + 95883264 = 23520^2 + 9792^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25999 + ... + 44430.

Almost surely, 2^649073664 is an apocalyptic number.

649073664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

649073664 is an abundant number, since it is smaller than the sum of its proper divisors (1225139066).

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

649073664 is a wasteful number, since it uses less digits than its factorization.

649073664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70455 (or 70434 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The square root of 649073664 is about 25476.9241471572. The cubic root of 649073664 is about 865.8274079261.

The spelling of 649073664 in words is "six hundred forty-nine million, seventy-three thousand, six hundred sixty-four".