138012540 has 24 divisors (see below), whose sum is σ = 386435280. Its totient is φ = 36803328.

The previous prime is 138012533. The next prime is 138012547. The reversal of 138012540 is 45210831.

138012540 = 4150² + 4151² + ... + 4157².

138012540 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138012533) and next prime (138012547).

It is a super-2 number, since 2×138012540² = 38094922394503200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 138012540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138012547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1150045 + ... + 1150164.

It is an arithmetic number, because the mean of its divisors is an integer number (16101470).

Almost surely, 2^138012540 is an apocalyptic number.

138012540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138012540 is an abundant number, since it is smaller than the sum of its proper divisors (248422740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138012540 is a wasteful number, since it uses less digits than its factorization.

138012540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2300221 (or 2300219 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 138012540 is about 11747.8738501909. The cubic root of 138012540 is about 516.7805774970.

The spelling of 138012540 in words is "one hundred thirty-eight million, twelve thousand, five hundred forty".