138668437752 has 128 divisors (see below), whose sum is σ = 375004392000. Its totient is φ = 42477281280.

The previous prime is 138668437711. The next prime is 138668437909. The reversal of 138668437752 is 257734866831.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93127824 + ... + 93129312.

Almost surely, 2^138668437752 is an apocalyptic number.

138668437752 is a gapful number since it is divisible by the number (12) 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 138668437752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187502196000).

138668437752 is an abundant number, since it is smaller than the sum of its proper divisors (236335954248).

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

138668437752 is a wasteful number, since it uses less digits than its factorization.

138668437752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2641 (or 2637 counting only the distinct ones).

The product of its digits is 40642560, while the sum is 60.

The spelling of 138668437752 in words is "one hundred thirty-eight billion, six hundred sixty-eight million, four hundred thirty-seven thousand, seven hundred fifty-two".