138905462988 has 72 divisors (see below), whose sum is σ = 367235432928. Its totient is φ = 44186300928.

The previous prime is 138905462963. The next prime is 138905462989. The reversal of 138905462988 is 889264509831.

138905462988 is a `hidden beast` number, since 1 + 3 + 8 + 9 + 0 + 546 + 2 + 9 + 88 = 666.

It is not an unprimeable number, because it can be changed into a prime (138905462989) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164806 + ... + 552242.

It is an arithmetic number, because the mean of its divisors is an integer number (5100492124).

Almost surely, 2^138905462988 is an apocalyptic number.

138905462988 is a gapful number since it is divisible by the number (18) 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 138905462988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183617716464).

138905462988 is an abundant number, since it is smaller than the sum of its proper divisors (228329969940).

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

138905462988 is a wasteful number, since it uses less digits than its factorization.

138905462988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387903 (or 387898 counting only the distinct ones).

The product of its (nonzero) digits is 29859840, while the sum is 63.

The spelling of 138905462988 in words is "one hundred thirty-eight billion, nine hundred five million, four hundred sixty-two thousand, nine hundred eighty-eight".