138791475 has 30 divisors (see below), whose sum is σ = 257093540. Its totient is φ = 74021040.

The previous prime is 138791467. The next prime is 138791489. The reversal of 138791475 is 574197831.

138791475 is a `hidden beast` number, since 13 + 87 + 91 + 475 = 666.

It is not a de Polignac number, because 138791475 - 2³ = 138791467 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 138791475.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 32245 + ... + 36294.

Almost surely, 2^138791475 is an apocalyptic number.

138791475 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138791475 is a deficient number, since it is larger than the sum of its proper divisors (118302065).

138791475 is an equidigital number, since it uses as much as digits as its factorization.

138791475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68561 (or 68547 counting only the distinct ones).

The product of its digits is 211680, while the sum is 45.

The square root of 138791475 is about 11780.9793735496. The cubic root of 138791475 is about 517.7509809672.

The spelling of 138791475 in words is "one hundred thirty-eight million, seven hundred ninety-one thousand, four hundred seventy-five".