138989831 has 2 divisors, whose sum is σ = 138989832. Its totient is φ = 138989830.

The previous prime is 138989819. The next prime is 138989843.

138989831 is nontrivially palindromic in base 10.

It is a balanced prime because it is at equal distance from previous prime (138989819) and next prime (138989843).

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 138989831 - 2²² = 134795527 is a prime.

It is a super-2 number, since 2×138989831² = 38636346242817122, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138989831.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138988831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69494915 + 69494916.

It is an arithmetic number, because the mean of its divisors is an integer number (69494916).

Almost surely, 2^138989831 is an apocalyptic number.

138989831 is a deficient number, since it is larger than the sum of its proper divisors (1).

138989831 is an equidigital number, since it uses as much as digits as its factorization.

138989831 is an evil number, because the sum of its binary digits is even.

The product of its digits is 373248, while the sum is 50.

The square root of 138989831 is about 11789.3948530024. The cubic root of 138989831 is about 517.9975141873.

The spelling of 138989831 in words is "one hundred thirty-eight million, nine hundred eighty-nine thousand, eight hundred thirty-one".