642439949976 has 48 divisors (see below), whose sum is σ = 1898118036360. Its totient is φ = 194678772480.

The previous prime is 642439949971. The next prime is 642439949989. The reversal of 642439949976 is 679949934246.

642439949976 is a `hidden beast` number, since 6 + 4 + 2 + 43 + 99 + 499 + 7 + 6 = 666.

642439949976 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642439949971) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 405579985 + ... + 405581568.

Almost surely, 2^642439949976 is an apocalyptic number.

642439949976 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

642439949976 is an abundant number, since it is smaller than the sum of its proper divisors (1255678086384).

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

642439949976 is a wasteful number, since it uses less digits than its factorization.

642439949976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811161576 (or 811161569 counting only the distinct ones).

The product of its digits is 634894848, while the sum is 72.

The spelling of 642439949976 in words is "six hundred forty-two billion, four hundred thirty-nine million, nine hundred forty-nine thousand, nine hundred seventy-six".