138831312 has 40 divisors (see below), whose sum is σ = 374243904. Its totient is φ = 44264704.

The previous prime is 138831293. The next prime is 138831313. The reversal of 138831312 is 213138831.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 138831312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138831313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61773 + ... + 63980.

Almost surely, 2^138831312 is an apocalyptic number.

138831312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

138831312 is an abundant number, since it is smaller than the sum of its proper divisors (235412592).

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

138831312 is a wasteful number, since it uses less digits than its factorization.

138831312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125787 (or 125781 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 138831312 is about 11782.6699860431. The cubic root of 138831312 is about 517.8005125223.

The spelling of 138831312 in words is "one hundred thirty-eight million, eight hundred thirty-one thousand, three hundred twelve".