138912500 has 36 divisors (see below), whose sum is σ = 303878988. Its totient is φ = 55560000.

The previous prime is 138912497. The next prime is 138912517. The reversal of 138912500 is 5219831.

It can be written as a sum of positive squares in 6 ways, for example, as 138203536 + 708964 = 11756^2 + 842^2 .

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 6944 + ... + 18056.

It is an arithmetic number, because the mean of its divisors is an integer number (8441083).

Almost surely, 2^138912500 is an apocalyptic number.

138912500 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 138912500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151939494).

138912500 is an abundant number, since it is smaller than the sum of its proper divisors (164966488).

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

138912500 is an equidigital number, since it uses as much as digits as its factorization.

138912500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11142 (or 11120 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 138912500 is about 11786.1147118124. The cubic root of 138912500 is about 517.9014287476.

The spelling of 138912500 in words is "one hundred thirty-eight million, nine hundred twelve thousand, five hundred".