138775680 has 160 divisors (see below), whose sum is σ = 495778140. Its totient is φ = 36993024.

The previous prime is 138775667. The next prime is 138775723. The reversal of 138775680 is 86577831.

138775680 is a `hidden beast` number, since 1 + 3 + 87 + 7 + 568 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 118200384 + 20575296 = 10872^2 + 4536^2 .

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 50502 + ... + 53178.

Almost surely, 2^138775680 is an apocalyptic number.

138775680 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 138775680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (247889070).

138775680 is an abundant number, since it is smaller than the sum of its proper divisors (357002460).

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

138775680 is an equidigital number, since it uses as much as digits as its factorization.

138775680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2708 (or 2687 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 45.

The square root of 138775680 is about 11780.3089942497. The cubic root of 138775680 is about 517.7313395424.

The spelling of 138775680 in words is "one hundred thirty-eight million, seven hundred seventy-five thousand, six hundred eighty".