6642979800 has 96 divisors (see below), whose sum is σ = 20614491600. Its totient is φ = 1769633280.

The previous prime is 6642979799. The next prime is 6642979813. The reversal of 6642979800 is 89792466.

It is a happy number.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 636222 + ... + 646578.

Almost surely, 2^6642979800 is an apocalyptic number.

6642979800 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6642979800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10307245800).

6642979800 is an abundant number, since it is smaller than the sum of its proper divisors (13971511800).

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

6642979800 is a wasteful number, since it uses less digits than its factorization.

6642979800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11445 (or 11436 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 51.

The square root of 6642979800 is about 81504.4771776373. The cubic root of 6642979800 is about 1879.8403931199.

The spelling of 6642979800 in words is "six billion, six hundred forty-two million, nine hundred seventy-nine thousand, eight hundred".