649606772640 has 96 divisors (see below), whose sum is σ = 2338584393600. Its totient is φ = 148481547264.

The previous prime is 649606772623. The next prime is 649606772653. The reversal of 649606772640 is 46277606946.

It is a tau number, because it is divible by the number of its divisors (96).

It is a hoax number, since the sum of its digits (57) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96664315 + ... + 96671034.

It is an arithmetic number, because the mean of its divisors is an integer number (24360254100).

Almost surely, 2^649606772640 is an apocalyptic number.

649606772640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

649606772640 is an abundant number, since it is smaller than the sum of its proper divisors (1688977620960).

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

649606772640 is a wasteful number, since it uses less digits than its factorization.

649606772640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193335374 (or 193335366 counting only the distinct ones).

The product of its (nonzero) digits is 18289152, while the sum is 57.

The spelling of 649606772640 in words is "six hundred forty-nine billion, six hundred six million, seven hundred seventy-two thousand, six hundred forty".