138915915840 has 224 divisors, whose sum is σ = 527762175360. Its totient is φ = 34194659328.

The previous prime is 138915915833. The next prime is 138915915847. The reversal of 138915915840 is 48519519831.

It is a happy number.

138915915840 is a `hidden beast` number, since 1 + 3 + 8 + 9 + 1 + 59 + 1 + 584 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (138915915833) and next prime (138915915847).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (138915915847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 506074 + ... + 730713.

It is an arithmetic number, because the mean of its divisors is an integer number (2356081140).

Almost surely, 2^138915915840 is an apocalyptic number.

138915915840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138915915840 is an abundant number, since it is smaller than the sum of its proper divisors (388846259520).

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

138915915840 is a wasteful number, since it uses less digits than its factorization.

138915915840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1236826 (or 1236810 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 54.

The spelling of 138915915840 in words is "one hundred thirty-eight billion, nine hundred fifteen million, nine hundred fifteen thousand, eight hundred forty".