138109860 has 240 divisors, whose sum is σ = 522023040. Its totient is φ = 29859840.

The previous prime is 138109859. The next prime is 138109883. The reversal of 138109860 is 68901831.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 79 ways as a sum of consecutive naturals, for example, 215140 + ... + 215780.

It is an arithmetic number, because the mean of its divisors is an integer number (2175096).

Almost surely, 2^138109860 is an apocalyptic number.

138109860 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 138109860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261011520).

138109860 is an abundant number, since it is smaller than the sum of its proper divisors (383913180).

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

138109860 is a wasteful number, since it uses less digits than its factorization.

138109860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688 (or 677 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 138109860 is about 11752.0151463483. The cubic root of 138109860 is about 516.9020188022.

The spelling of 138109860 in words is "one hundred thirty-eight million, one hundred nine thousand, eight hundred sixty".