138679658 has 16 divisors (see below), whose sum is σ = 224749896. Its totient is φ = 63797760.

The previous prime is 138679649. The next prime is 138679669. The reversal of 138679658 is 856976831.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 80874049 + 57805609 = 8993^2 + 7603^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 383 + ... + 16658.

Almost surely, 2^138679658 is an apocalyptic number.

138679658 is a deficient number, since it is larger than the sum of its proper divisors (86070238).

138679658 is a wasteful number, since it uses less digits than its factorization.

138679658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17369.

The product of its digits is 2177280, while the sum is 53.

The square root of 138679658 is about 11776.2327592486. The cubic root of 138679658 is about 517.6119020226.

The spelling of 138679658 in words is "one hundred thirty-eight million, six hundred seventy-nine thousand, six hundred fifty-eight".