138751217955 has 24 divisors (see below), whose sum is σ = 274859556192. Its totient is φ = 63429128064.

The previous prime is 138751217911. The next prime is 138751218037. The reversal of 138751217955 is 559712157831.

138751217955 is a `hidden beast` number, since 1 + 3 + 8 + 7 + 512 + 1 + 79 + 55 = 666.

It is not a de Polignac number, because 138751217955 - 2⁹ = 138751217443 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 220239714 + ... + 220240343.

It is an arithmetic number, because the mean of its divisors is an integer number (11452481508).

Almost surely, 2^138751217955 is an apocalyptic number.

138751217955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138751217955 is a deficient number, since it is larger than the sum of its proper divisors (136108338237).

138751217955 is a wasteful number, since it uses less digits than its factorization.

138751217955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440480075 (or 440480072 counting only the distinct ones).

The product of its digits is 2646000, while the sum is 54.

It can be divided in two parts, 13875121 and 7955, that added together give a square (13883076 = 3726²).

The spelling of 138751217955 in words is "one hundred thirty-eight billion, seven hundred fifty-one million, two hundred seventeen thousand, nine hundred fifty-five".