138889798 has 4 divisors (see below), whose sum is σ = 208334700. Its totient is φ = 69444898.

The previous prime is 138889789. The next prime is 138889799. The reversal of 138889798 is 897988831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 897988831 = 137 ⋅6554663.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138889799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34722448 + ... + 34722451.

It is an arithmetic number, because the mean of its divisors is an integer number (52083675).

Almost surely, 2^138889798 is an apocalyptic number.

138889798 is a deficient number, since it is larger than the sum of its proper divisors (69444902).

138889798 is an equidigital number, since it uses as much as digits as its factorization.

138889798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69444901.

The product of its digits is 6967296, while the sum is 61.

The square root of 138889798 is about 11785.1515900306. The cubic root of 138889798 is about 517.8732142510.

The spelling of 138889798 in words is "one hundred thirty-eight million, eight hundred eighty-nine thousand, seven hundred ninety-eight".