138122640 has 60 divisors (see below), whose sum is σ = 463864284. Its totient is φ = 36832512.

The previous prime is 138122629. The next prime is 138122653. The reversal of 138122640 is 46221831.

138122640 is a `hidden beast` number, since 1 + 3 + 8 + 12 + 2 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 94245264 + 43877376 = 9708^2 + 6624^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95199 + ... + 96638.

Almost surely, 2^138122640 is an apocalyptic number.

138122640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138122640 is an abundant number, since it is smaller than the sum of its proper divisors (325741644).

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

138122640 is a wasteful number, since it uses less digits than its factorization.

138122640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191856 (or 191847 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 138122640 is about 11752.5588703056. The cubic root of 138122640 is about 516.9179621583.

The spelling of 138122640 in words is "one hundred thirty-eight million, one hundred twenty-two thousand, six hundred forty".