138137508 has 48 divisors (see below), whose sum is σ = 358792000. Its totient is φ = 45961344.

The previous prime is 138137501. The next prime is 138137509. The reversal of 138137508 is 805731831.

138137508 is a `hidden beast` number, since 13 + 8 + 137 + 508 = 666.

It is a super-2 number, since 2×138137508² = 38163942232900128, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (138137501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92028 + ... + 93516.

Almost surely, 2^138137508 is an apocalyptic number.

138137508 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

138137508 is an abundant number, since it is smaller than the sum of its proper divisors (220654492).

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

138137508 is a wasteful number, since it uses less digits than its factorization.

138137508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2361 (or 2353 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 138137508 is about 11753.1913963825. The cubic root of 138137508 is about 516.9365091069.

It can be divided in two parts, 13813 and 7508, that added together give a triangular number (21321 = T₂₀₆).

The spelling of 138137508 in words is "one hundred thirty-eight million, one hundred thirty-seven thousand, five hundred eight".