138400531200 has 864 divisors, whose sum is σ = 536515660800. Its totient is φ = 34840903680.

The previous prime is 138400531193. The next prime is 138400531211. The reversal of 138400531200 is 2135004831.

It is a happy number.

138400531200 is a `hidden beast` number, since 1 + 3 + 8 + 400 + 53 + 1 + 200 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 385516621 + ... + 385516979.

It is an arithmetic number, because the mean of its divisors is an integer number (620967200).

Almost surely, 2^138400531200 is an apocalyptic number.

138400531200 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 138400531200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268257830400).

138400531200 is an abundant number, since it is smaller than the sum of its proper divisors (398115129600).

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

138400531200 is a wasteful number, since it uses less digits than its factorization.

138400531200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The spelling of 138400531200 in words is "one hundred thirty-eight billion, four hundred million, five hundred thirty-one thousand, two hundred".