138187992 has 32 divisors (see below), whose sum is σ = 345761280. Its totient is φ = 46023840.

The previous prime is 138187967. The next prime is 138188003. The reversal of 138187992 is 299781831.

It is a super-2 number, since 2×138187992² = 38191842265984128, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48117 + ... + 50907.

It is an arithmetic number, because the mean of its divisors is an integer number (10805040).

Almost surely, 2^138187992 is an apocalyptic number.

138187992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

138187992 is an abundant number, since it is smaller than the sum of its proper divisors (207573288).

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

138187992 is a wasteful number, since it uses less digits than its factorization.

138187992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4863 (or 4859 counting only the distinct ones).

The product of its digits is 217728, while the sum is 48.

The square root of 138187992 is about 11755.3388721891. The cubic root of 138187992 is about 516.9994749747. Note that the first 3 decimals are identical.

The spelling of 138187992 in words is "one hundred thirty-eight million, one hundred eighty-seven thousand, nine hundred ninety-two".