138866686 has 24 divisors (see below), whose sum is σ = 252847440. Its totient is φ = 56925792.

The previous prime is 138866671. The next prime is 138866711. The reversal of 138866686 is 686668831.

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, 28551 + ... + 33058.

It is an arithmetic number, because the mean of its divisors is an integer number (10535310).

Almost surely, 2^138866686 is an apocalyptic number.

138866686 is a deficient number, since it is larger than the sum of its proper divisors (113980754).

138866686 is a wasteful number, since it uses less digits than its factorization.

138866686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61648 (or 61641 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 52.

The square root of 138866686 is about 11784.1709933283. The cubic root of 138866686 is about 517.8444870398.

The spelling of 138866686 in words is "one hundred thirty-eight million, eight hundred sixty-six thousand, six hundred eighty-six".