643403678365500 has 96 divisors (see below), whose sum is σ = 2017713935415360. Its totient is φ = 158376290054400.

The previous prime is 643403678365421. The next prime is 643403678365529. The reversal of 643403678365500 is 5563876304346.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16497510715 + ... + 16497549714.

It is an arithmetic number, because the mean of its divisors is an integer number (21017853493910).

Almost surely, 2^{643403678365500} is an apocalyptic number.

643403678365500 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

643403678365500 is an abundant number, since it is smaller than the sum of its proper divisors (1374310257049860).

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

643403678365500 is a wasteful number, since it uses less digits than its factorization.

643403678365500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32995060464 (or 32995060452 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 60.

The spelling of 643403678365500 in words is "six hundred forty-three trillion, four hundred three billion, six hundred seventy-eight million, three hundred sixty-five thousand, five hundred".