138787889 has 4 divisors (see below), whose sum is σ = 140742720. Its totient is φ = 136833060.

The previous prime is 138787861. The next prime is 138787921. The reversal of 138787889 is 988787831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 988787831 = 11159 ⋅88609.

It is a cyclic number.

It is not a de Polignac number, because 138787889 - 2⁸ = 138787633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138787849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 977309 + ... + 977450.

It is an arithmetic number, because the mean of its divisors is an integer number (35185680).

Almost surely, 2^138787889 is an apocalyptic number.

It is an amenable number.

138787889 is a deficient number, since it is larger than the sum of its proper divisors (1954831).

138787889 is an equidigital number, since it uses as much as digits as its factorization.

138787889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1954830.

The product of its digits is 5419008, while the sum is 59.

The square root of 138787889 is about 11780.8271780890. The cubic root of 138787889 is about 517.7465218293.

The spelling of 138787889 in words is "one hundred thirty-eight million, seven hundred eighty-seven thousand, eight hundred eighty-nine".