64890631680 has 160 divisors (see below), whose sum is σ = 237082754304. Its totient is φ = 14832132096.

The previous prime is 64890631661. The next prime is 64890631691. The reversal of 64890631680 is 8613609846.

It is a tau number, because it is divible by the number of its divisors (160).

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, 549762 + ... + 657281.

Almost surely, 2^64890631680 is an apocalyptic number.

64890631680 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64890631680 is an abundant number, since it is smaller than the sum of its proper divisors (172192122624).

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

64890631680 is a wasteful number, since it uses less digits than its factorization.

64890631680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1207076 (or 1207060 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 51.

The spelling of 64890631680 in words is "sixty-four billion, eight hundred ninety million, six hundred thirty-one thousand, six hundred eighty".