138930885 has 24 divisors (see below), whose sum is σ = 254980440. Its totient is φ = 69737472.

The previous prime is 138930881. The next prime is 138930887. The reversal of 138930885 is 588039831.

138930885 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 33108516 + 105822369 = 5754^2 + 10287^2 .

It is not a de Polignac number, because 138930885 - 2² = 138930881 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 138930885.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138930881) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 90040 + ... + 91569.

It is an arithmetic number, because the mean of its divisors is an integer number (10624185).

Almost surely, 2^138930885 is an apocalyptic number.

138930885 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138930885 is a deficient number, since it is larger than the sum of its proper divisors (116049555).

138930885 is a wasteful number, since it uses less digits than its factorization.

138930885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181637 (or 181634 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 138930885 is about 11786.8946292058. The cubic root of 138930885 is about 517.9242757382.

The spelling of 138930885 in words is "one hundred thirty-eight million, nine hundred thirty thousand, eight hundred eighty-five".