138861240 has 64 divisors (see below), whose sum is σ = 476098560. Its totient is φ = 31739520.

The previous prime is 138861211. The next prime is 138861263. The reversal of 138861240 is 42168831.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81816 + ... + 83495.

It is an arithmetic number, because the mean of its divisors is an integer number (7439040).

Almost surely, 2^138861240 is an apocalyptic number.

138861240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138861240 is an abundant number, since it is smaller than the sum of its proper divisors (337237320).

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

138861240 is a wasteful number, since it uses less digits than its factorization.

138861240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165332 (or 165328 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 138861240 is about 11783.9399183804. The cubic root of 138861240 is about 517.8377174345.

The spelling of 138861240 in words is "one hundred thirty-eight million, eight hundred sixty-one thousand, two hundred forty".