138311775 has 72 divisors (see below), whose sum is σ = 285633504. Its totient is φ = 62668800.

The previous prime is 138311687. The next prime is 138311839. The reversal of 138311775 is 577113831.

It is a happy number.

It is not a de Polignac number, because 138311775 - 2²⁰ = 137263199 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 215455 + ... + 216095.

It is an arithmetic number, because the mean of its divisors is an integer number (3967132).

Almost surely, 2^138311775 is an apocalyptic number.

138311775 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138311775 is an abundant number, since it is smaller than the sum of its proper divisors (147321729).

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

138311775 is a wasteful number, since it uses less digits than its factorization.

138311775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 801 (or 793 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 138311775 is about 11760.6026631291. The cubic root of 138311775 is about 517.1537977114.

The spelling of 138311775 in words is "one hundred thirty-eight million, three hundred eleven thousand, seven hundred seventy-five".