6642491904 has 240 divisors, whose sum is σ = 19763377920. Its totient is φ = 2146959360.

The previous prime is 6642491897. The next prime is 6642491929. The reversal of 6642491904 is 4091942466.

It is a self number, because there is not a number n which added to its sum of digits gives 6642491904.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25846144 + ... + 25846400.

It is an arithmetic number, because the mean of its divisors is an integer number (82347408).

Almost surely, 2^6642491904 is an apocalyptic number.

6642491904 is a gapful number since it is divisible by the number (64) 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 6642491904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9881688960).

6642491904 is an abundant number, since it is smaller than the sum of its proper divisors (13120886016).

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

6642491904 is a wasteful number, since it uses less digits than its factorization.

6642491904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431 (or 412 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The square root of 6642491904 is about 81501.4840601078. The cubic root of 6642491904 is about 1879.7943701457.

The spelling of 6642491904 in words is "six billion, six hundred forty-two million, four hundred ninety-one thousand, nine hundred four".