138780015 has 16 divisors (see below), whose sum is σ = 242234496. Its totient is φ = 67287200.

The previous prime is 138779983. The next prime is 138780071. The reversal of 138780015 is 510087831.

It is not a de Polignac number, because 138780015 - 2⁵ = 138779983 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 420381 + ... + 420710.

It is an arithmetic number, because the mean of its divisors is an integer number (15139656).

Almost surely, 2^138780015 is an apocalyptic number.

138780015 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138780015 is a deficient number, since it is larger than the sum of its proper divisors (103454481).

138780015 is a wasteful number, since it uses less digits than its factorization.

138780015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841110.

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 138780015 is about 11780.4929862888. The cubic root of 138780015 is about 517.7367303572.

The spelling of 138780015 in words is "one hundred thirty-eight million, seven hundred eighty thousand, fifteen".