138899855 has 4 divisors (see below), whose sum is σ = 166679832. Its totient is φ = 111119880.

The previous prime is 138899851. The next prime is 138899857. The reversal of 138899855 is 558998831.

138899855 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138899855 - 2² = 138899851 is a prime.

It is a super-3 number, since 3×138899855³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138899855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138899851) 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, 13889981 + ... + 13889990.

It is an arithmetic number, because the mean of its divisors is an integer number (41669958).

Almost surely, 2^138899855 is an apocalyptic number.

138899855 is a deficient number, since it is larger than the sum of its proper divisors (27779977).

138899855 is an equidigital number, since it uses as much as digits as its factorization.

138899855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27779976.

The product of its digits is 3110400, while the sum is 56.

The square root of 138899855 is about 11785.5782632843. The cubic root of 138899855 is about 517.8857136697.

The spelling of 138899855 in words is "one hundred thirty-eight million, eight hundred ninety-nine thousand, eight hundred fifty-five".