138781400 has 48 divisors (see below), whose sum is σ = 325191240. Its totient is φ = 55078400.

The previous prime is 138781399. The next prime is 138781427. The reversal of 138781400 is 4187831.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23552 + ... + 28848.

Almost surely, 2^138781400 is an apocalyptic number.

138781400 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 138781400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162595620).

138781400 is an abundant number, since it is smaller than the sum of its proper divisors (186409840).

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

138781400 is a wasteful number, since it uses less digits than its factorization.

138781400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5444 (or 5435 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 138781400 is about 11780.5517697602. The cubic root of 138781400 is about 517.7384526585.

The spelling of 138781400 in words is "one hundred thirty-eight million, seven hundred eighty-one thousand, four hundred".