138658 has 8 divisors (see below), whose sum is σ = 224028. Its totient is φ = 63984.

The previous prime is 138647. The next prime is 138661. The reversal of 138658 is 856831.

It can be written as a sum of positive squares in 2 ways, for example, as 134689 + 3969 = 367^2 + 63^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2641 + ... + 2692.

2¹³⁸⁶⁵⁸ is an apocalyptic number.

138658 is a deficient number, since it is larger than the sum of its proper divisors (85370).

138658 is a wasteful number, since it uses less digits than its factorization.

138658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5348.

The product of its digits is 5760, while the sum is 31.

The square root of 138658 is about 372.3680974520. The cubic root of 138658 is about 51.7584954975.

It can be divided in two parts, 1386 and 58, that added together give a square (1444 = 38²).

The spelling of 138658 in words is "one hundred thirty-eight thousand, six hundred fifty-eight".