642642636900 has 72 divisors (see below), whose sum is σ = 2028413860704. Its totient is φ = 155792153600.

The previous prime is 642642636869. The next prime is 642642636907. The reversal of 642642636900 is 9636246246.

It is a super-2 number, since 2×642642636900² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 642642636900.

It is not an unprimeable number, because it can be changed into a prime (642642636907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 97366797 + ... + 97373396.

It is an arithmetic number, because the mean of its divisors is an integer number (28172414732).

Almost surely, 2^642642636900 is an apocalyptic number.

642642636900 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

642642636900 is an abundant number, since it is smaller than the sum of its proper divisors (1385771223804).

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

642642636900 is a wasteful number, since it uses less digits than its factorization.

642642636900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194740221 (or 194740214 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 48.

The spelling of 642642636900 in words is "six hundred forty-two billion, six hundred forty-two million, six hundred thirty-six thousand, nine hundred".