18689621100 has 144 divisors (see below), whose sum is σ = 54954982656. Its totient is φ = 4903136000.

The previous prime is 18689621099. The next prime is 18689621113. The reversal of 18689621100 is 112698681.

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, 17614570 + ... + 17615630.

It is an arithmetic number, because the mean of its divisors is an integer number (381631824).

Almost surely, 2^18689621100 is an apocalyptic number.

18689621100 is a gapful number since it is divisible by the number (10) 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 18689621100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27477491328).

18689621100 is an abundant number, since it is smaller than the sum of its proper divisors (36265361556).

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

18689621100 is a wasteful number, since it uses less digits than its factorization.

18689621100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976 (or 1969 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 42.

The spelling of 18689621100 in words is "eighteen billion, six hundred eighty-nine million, six hundred twenty-one thousand, one hundred".