138391975 has 12 divisors (see below), whose sum is σ = 171770256. Its totient is φ = 110607680.

The previous prime is 138391969. The next prime is 138391997. The reversal of 138391975 is 579193831.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-138391975 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33894 + ... + 37756.

It is an arithmetic number, because the mean of its divisors is an integer number (14314188).

Almost surely, 2^138391975 is an apocalyptic number.

138391975 is a deficient number, since it is larger than the sum of its proper divisors (33378281).

138391975 is a wasteful number, since it uses less digits than its factorization.

138391975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5306 (or 5301 counting only the distinct ones).

The product of its digits is 204120, while the sum is 46.

The square root of 138391975 is about 11764.0118582055. The cubic root of 138391975 is about 517.2537355043.

The spelling of 138391975 in words is "one hundred thirty-eight million, three hundred ninety-one thousand, nine hundred seventy-five".