138855555 has 24 divisors (see below), whose sum is σ = 241064928. Its totient is φ = 73938816.

The previous prime is 138855547. The next prime is 138855571. The reversal of 138855555 is 555558831.

It is a happy number.

138855555 is a `hidden beast` number, since 13 + 8 + 85 + 5 + 555 = 666.

It is not a de Polignac number, because 138855555 - 2³ = 138855547 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 138855555.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31359 + ... + 35511.

It is an arithmetic number, because the mean of its divisors is an integer number (10044372).

Almost surely, 2^138855555 is an apocalyptic number.

138855555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138855555 is a deficient number, since it is larger than the sum of its proper divisors (102209373).

138855555 is a wasteful number, since it uses less digits than its factorization.

138855555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4907 (or 4904 counting only the distinct ones).

The product of its digits is 600000, while the sum is 45.

The square root of 138855555 is about 11783.6986977774. The cubic root of 138855555 is about 517.8306505535.

The spelling of 138855555 in words is "one hundred thirty-eight million, eight hundred fifty-five thousand, five hundred fifty-five".