668138495100 has 144 divisors (see below), whose sum is σ = 1973592432000. Its totient is φ = 174456172800.

The previous prime is 668138495083. The next prime is 668138495113. The reversal of 668138495100 is 1594831866.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7891995 + ... + 7976205.

It is an arithmetic number, because the mean of its divisors is an integer number (13705503000).

Almost surely, 2^668138495100 is an apocalyptic number.

668138495100 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 668138495100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (986796216000).

668138495100 is an abundant number, since it is smaller than the sum of its proper divisors (1305453936900).

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

668138495100 is a wasteful number, since it uses less digits than its factorization.

668138495100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84780 (or 84773 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 51.

The spelling of 668138495100 in words is "six hundred sixty-eight billion, one hundred thirty-eight million, four hundred ninety-five thousand, one hundred".