642658432444 has 24 divisors (see below), whose sum is σ = 1285333872480. Its totient is φ = 275421398016.

The previous prime is 642658432421. The next prime is 642658432469. The reversal of 642658432444 is 444234856246.

It is a junction number, because it is equal to n+sod(n) for n = 642658432391 and 642658432400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3880812 + ... + 4043020.

It is an arithmetic number, because the mean of its divisors is an integer number (53555578020).

Almost surely, 2^642658432444 is an apocalyptic number.

It is an amenable number.

642658432444 is an abundant number, since it is smaller than the sum of its proper divisors (642675440036).

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

642658432444 is a wasteful number, since it uses less digits than its factorization.

642658432444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303717 (or 303715 counting only the distinct ones).

The product of its digits is 17694720, while the sum is 52.

The spelling of 642658432444 in words is "six hundred forty-two billion, six hundred fifty-eight million, four hundred thirty-two thousand, four hundred forty-four".