138944400 has 360 divisors, whose sum is σ = 552152160. Its totient is φ = 29675520.

The previous prime is 138944389. The next prime is 138944401. The reversal of 138944400 is 4449831.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (138944401) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 999531 + ... + 999669.

It is an arithmetic number, because the mean of its divisors is an integer number (1533756).

Almost surely, 2^138944400 is an apocalyptic number.

138944400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138944400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276076080).

138944400 is an abundant number, since it is smaller than the sum of its proper divisors (413207760).

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

138944400 is a wasteful number, since it uses less digits than its factorization.

138944400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 138944400 is about 11787.4679214834. The cubic root of 138944400 is about 517.9410695073.

The spelling of 138944400 in words is "one hundred thirty-eight million, nine hundred forty-four thousand, four hundred".