648429686640 has 80 divisors (see below), whose sum is σ = 2233480039200. Its totient is φ = 172914582528.

The previous prime is 648429686591. The next prime is 648429686657. The reversal of 648429686640 is 46686924846.

648429686640 is a `hidden beast` number, since 6 + 484 + 2 + 96 + 8 + 6 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×648429686640² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a congruent number.

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, 150097305 + ... + 150101624.

It is an arithmetic number, because the mean of its divisors is an integer number (27918500490).

Almost surely, 2^648429686640 is an apocalyptic number.

648429686640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

648429686640 is an abundant number, since it is smaller than the sum of its proper divisors (1585050352560).

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

648429686640 is a wasteful number, since it uses less digits than its factorization.

648429686640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300198951 (or 300198939 counting only the distinct ones).

The product of its (nonzero) digits is 95551488, while the sum is 63.

The spelling of 648429686640 in words is "six hundred forty-eight billion, four hundred twenty-nine million, six hundred eighty-six thousand, six hundred forty".