138799994 has 4 divisors (see below), whose sum is σ = 208199994. Its totient is φ = 69399996.

The previous prime is 138799981. The next prime is 138800017. The reversal of 138799994 is 499997831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 499997831 = 4327 ⋅115553.

It can be written as a sum of positive squares in only one way, i.e., 113145769 + 25654225 = 10637^2 + 5065^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34699997 + ... + 34700000.

Almost surely, 2^138799994 is an apocalyptic number.

138799994 is a deficient number, since it is larger than the sum of its proper divisors (69400000).

138799994 is an equidigital number, since it uses as much as digits as its factorization.

138799994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69399999.

The product of its digits is 4408992, while the sum is 59.

The square root of 138799994 is about 11781.3409253786. The cubic root of 138799994 is about 517.7615739098.

The spelling of 138799994 in words is "one hundred thirty-eight million, seven hundred ninety-nine thousand, nine hundred ninety-four".