642690636848 has 80 divisors (see below), whose sum is σ = 1417436882400. Its totient is φ = 279848079360.

The previous prime is 642690636827. The next prime is 642690636851. The reversal of 642690636848 is 848636096246.

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, 615038 + ... + 1289826.

It is an arithmetic number, because the mean of its divisors is an integer number (17717961030).

Almost surely, 2^642690636848 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642690636848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (708718441200).

642690636848 is an abundant number, since it is smaller than the sum of its proper divisors (774746245552).

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

642690636848 is a wasteful number, since it uses less digits than its factorization.

642690636848 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 675070 (or 675064 counting only the distinct ones).

The product of its (nonzero) digits is 71663616, while the sum is 62.

The spelling of 642690636848 in words is "six hundred forty-two billion, six hundred ninety million, six hundred thirty-six thousand, eight hundred forty-eight".