138415680 has 168 divisors, whose sum is σ = 512853432. Its totient is φ = 34062336.

The previous prime is 138415657. The next prime is 138415691. The reversal of 138415680 is 86514831.

138415680 is a `hidden beast` number, since 13 + 84 + 1 + 568 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1806336 + 136609344 = 1344^2 + 11688^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35592 + ... + 39288.

It is an arithmetic number, because the mean of its divisors is an integer number (3052699).

Almost surely, 2^138415680 is an apocalyptic number.

138415680 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 138415680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (256426716).

138415680 is an abundant number, since it is smaller than the sum of its proper divisors (374437752).

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

138415680 is a wasteful number, since it uses less digits than its factorization.

138415680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733 (or 3720 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 138415680 is about 11765.0193370007. The cubic root of 138415680 is about 517.2832670813.

The spelling of 138415680 in words is "one hundred thirty-eight million, four hundred fifteen thousand, six hundred eighty".