138709812 has 24 divisors (see below), whose sum is σ = 323902656. Its totient is φ = 46201408.

The previous prime is 138709811. The next prime is 138709877. The reversal of 138709812 is 218907831.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138709811) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15688 + ... + 22880.

It is an arithmetic number, because the mean of its divisors is an integer number (13495944).

Almost surely, 2^138709812 is an apocalyptic number.

138709812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

138709812 is an abundant number, since it is smaller than the sum of its proper divisors (185192844).

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

138709812 is a wasteful number, since it uses less digits than its factorization.

138709812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8807 (or 8805 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 138709812 is about 11777.5129802518. The cubic root of 138709812 is about 517.6494151864.

The spelling of 138709812 in words is "one hundred thirty-eight million, seven hundred nine thousand, eight hundred twelve".