138668386 has 16 divisors (see below), whose sum is σ = 210220920. Its totient is φ = 68598400.

The previous prime is 138668351. The next prime is 138668393. The reversal of 138668386 is 683866831.

It is a happy number.

138668386 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 58905625 + 79762761 = 7675^2 + 8931^2 .

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, 105936 + ... + 107236.

Almost surely, 2^138668386 is an apocalyptic number.

138668386 is a deficient number, since it is larger than the sum of its proper divisors (71552534).

138668386 is a wasteful number, since it uses less digits than its factorization.

138668386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1829.

The product of its digits is 995328, while the sum is 49.

The square root of 138668386 is about 11775.7541584393. The cubic root of 138668386 is about 517.5978776647.

The spelling of 138668386 in words is "one hundred thirty-eight million, six hundred sixty-eight thousand, three hundred eighty-six".