108609621138 has 24 divisors (see below), whose sum is σ = 235335065628. Its totient is φ = 36201019392.

The previous prime is 108609621137. The next prime is 108609621161. The reversal of 108609621138 is 831126906801.

108609621138 is a `hidden beast` number, since 1 + 0 + 8 + 6 + 0 + 9 + 621 + 13 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 78010165809 + 30599455329 = 279303^2 + 174927^2 .

It is a junction number, because it is equal to n+sod(n) for n = 108609621093 and 108609621102.

It is not an unprimeable number, because it can be changed into a prime (108609621137) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 139170 + ... + 486402.

Almost surely, 2^108609621138 is an apocalyptic number.

108609621138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

108609621138 is an abundant number, since it is smaller than the sum of its proper divisors (126725444490).

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

108609621138 is a wasteful number, since it uses less digits than its factorization.

108609621138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364618 (or 364615 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The spelling of 108609621138 in words is "one hundred eight billion, six hundred nine million, six hundred twenty-one thousand, one hundred thirty-eight".