138813615 has 64 divisors (see below), whose sum is σ = 254592000. Its totient is φ = 71736192.

The previous prime is 138813611. The next prime is 138813641. The reversal of 138813615 is 516318831.

138813615 is a `hidden beast` number, since 1 + 38 + 8 + 1 + 3 + 615 = 666.

It is not a de Polignac number, because 138813615 - 2² = 138813611 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138813615.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138813611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 931561 + ... + 931709.

It is an arithmetic number, because the mean of its divisors is an integer number (3978000).

Almost surely, 2^138813615 is an apocalyptic number.

138813615 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138813615 is a deficient number, since it is larger than the sum of its proper divisors (115778385).

138813615 is a wasteful number, since it uses less digits than its factorization.

138813615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333 (or 327 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 138813615 is about 11781.9189863112. The cubic root of 138813615 is about 517.7785100290.

The spelling of 138813615 in words is "one hundred thirty-eight million, eight hundred thirteen thousand, six hundred fifteen".