643527766164 has 48 divisors (see below), whose sum is σ = 1507279063808. Its totient is φ = 213693234048.

The previous prime is 643527766153. The next prime is 643527766201. The reversal of 643527766164 is 461667725346.

It is a happy number.

643527766164 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 20370309 + ... + 20401875.

Almost surely, 2^643527766164 is an apocalyptic number.

It is an amenable number.

643527766164 is an abundant number, since it is smaller than the sum of its proper divisors (863751297644).

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

643527766164 is a wasteful number, since it uses less digits than its factorization.

643527766164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37984 (or 37982 counting only the distinct ones).

The product of its digits is 30481920, while the sum is 57.

The spelling of 643527766164 in words is "six hundred forty-three billion, five hundred twenty-seven million, seven hundred sixty-six thousand, one hundred sixty-four".