138407888 has 20 divisors (see below), whose sum is σ = 269969700. Its totient is φ = 68738304.

The previous prime is 138407887. The next prime is 138407891. The reversal of 138407888 is 888704831.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 37847104 + 100560784 = 6152^2 + 10028^2 .

It is a super-3 number, since 3×138407888³ (a number of 25 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138407887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26645 + ... + 31412.

It is an arithmetic number, because the mean of its divisors is an integer number (13498485).

Almost surely, 2^138407888 is an apocalyptic number.

It is an amenable number.

138407888 is a deficient number, since it is larger than the sum of its proper divisors (131561812).

138407888 is a wasteful number, since it uses less digits than its factorization.

138407888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58214 (or 58208 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 47.

The square root of 138407888 is about 11764.6881811632. The cubic root of 138407888 is about 517.2735602165.

The spelling of 138407888 in words is "one hundred thirty-eight million, four hundred seven thousand, eight hundred eighty-eight".