138491938 has 16 divisors (see below), whose sum is σ = 224687736. Its totient is φ = 63642240.

The previous prime is 138491933. The next prime is 138491953. The reversal of 138491938 is 839194831.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 108930969 + 29560969 = 10437^2 + 5437^2 .

It is not an unprimeable number, because it can be changed into a prime (138491933) 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, 5373 + ... + 17488.

Almost surely, 2^138491938 is an apocalyptic number.

138491938 is a deficient number, since it is larger than the sum of its proper divisors (86195798).

138491938 is a wasteful number, since it uses less digits than its factorization.

138491938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23109.

The product of its digits is 186624, while the sum is 46.

The square root of 138491938 is about 11768.2597693967. The cubic root of 138491938 is about 517.3782460734.

The spelling of 138491938 in words is "one hundred thirty-eight million, four hundred ninety-one thousand, nine hundred thirty-eight".