138812440 has 32 divisors (see below), whose sum is σ = 336354480. Its totient is φ = 51253632.

The previous prime is 138812431. The next prime is 138812441. The reversal of 138812440 is 44218831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138812441) 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, 132954 + ... + 133993.

Almost surely, 2^138812440 is an apocalyptic number.

138812440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138812440 is an abundant number, since it is smaller than the sum of its proper divisors (197542040).

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

138812440 is a wasteful number, since it uses less digits than its factorization.

138812440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266971 (or 266967 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 31.

The square root of 138812440 is about 11781.8691216632. The cubic root of 138812440 is about 517.7770490977. Note that the first 3 decimals are identical.

The spelling of 138812440 in words is "one hundred thirty-eight million, eight hundred twelve thousand, four hundred forty".