138989 has 4 divisors (see below), whose sum is σ = 145056. Its totient is φ = 132924.

The previous prime is 138977. The next prime is 139021. The reversal of 138989 is 989831.

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.

It is a cyclic number.

It is not a de Polignac number, because 138989 - 2¹⁶ = 73453 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138959) 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 in 3 ways as a sum of consecutive naturals, for example, 2999 + ... + 3044.

It is an arithmetic number, because the mean of its divisors is an integer number (36264).

2¹³⁸⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

138989 is a deficient number, since it is larger than the sum of its proper divisors (6067).

138989 is an equidigital number, since it uses as much as digits as its factorization.

138989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6066.

The product of its digits is 15552, while the sum is 38.

The square root of 138989 is about 372.8122852053. The cubic root of 138989 is about 51.7996481841.

The spelling of 138989 in words is "one hundred thirty-eight thousand, nine hundred eighty-nine".