138987899 has 8 divisors (see below), whose sum is σ = 141108240. Its totient is φ = 136878336.

The previous prime is 138987859. The next prime is 138987929. The reversal of 138987899 is 998789831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138987899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138987859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25487 + ... + 30455.

It is an arithmetic number, because the mean of its divisors is an integer number (17638530).

Almost surely, 2^138987899 is an apocalyptic number.

138987899 is a deficient number, since it is larger than the sum of its proper divisors (2120341).

138987899 is an equidigital number, since it uses as much as digits as its factorization.

138987899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5389.

The product of its digits is 7838208, while the sum is 62.

The square root of 138987899 is about 11789.3129146698. The cubic root of 138987899 is about 517.9951140697.

The spelling of 138987899 in words is "one hundred thirty-eight million, nine hundred eighty-seven thousand, eight hundred ninety-nine".