138660238 has 32 divisors (see below), whose sum is σ = 224472384. Its totient is φ = 64069632.

The previous prime is 138660167. The next prime is 138660257. The reversal of 138660238 is 832066831.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a junction number, because it is equal to n+sod(n) for n = 138660197 and 138660206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 437256 + ... + 437572.

It is an arithmetic number, because the mean of its divisors is an integer number (7014762).

Almost surely, 2^138660238 is an apocalyptic number.

138660238 is a deficient number, since it is larger than the sum of its proper divisors (85812146).

138660238 is a wasteful number, since it uses less digits than its factorization.

138660238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636.

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 138660238 is about 11775.4081882540. The cubic root of 138660238 is about 517.5877396411.

The spelling of 138660238 in words is "one hundred thirty-eight million, six hundred sixty thousand, two hundred thirty-eight".