138404986 has 16 divisors (see below), whose sum is σ = 211111488. Its totient is φ = 68040000.

The previous prime is 138404983. The next prime is 138404993. The reversal of 138404986 is 689404831.

It is not an unprimeable number, because it can be changed into a prime (138404983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60361 + ... + 62611.

It is an arithmetic number, because the mean of its divisors is an integer number (13194468).

Almost surely, 2^138404986 is an apocalyptic number.

138404986 is a deficient number, since it is larger than the sum of its proper divisors (72706502).

138404986 is a wasteful number, since it uses less digits than its factorization.

138404986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2757.

The product of its (nonzero) digits is 165888, while the sum is 43.

The square root of 138404986 is about 11764.5648453311. The cubic root of 138404986 is about 517.2699449641.

The spelling of 138404986 in words is "one hundred thirty-eight million, four hundred four thousand, nine hundred eighty-six".