138399272 has 64 divisors (see below), whose sum is σ = 293932800. Its totient is φ = 60544000.

The previous prime is 138399269. The next prime is 138399293. The reversal of 138399272 is 272993831.

It is a happy number.

138399272 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 320897 + ... + 321327.

It is an arithmetic number, because the mean of its divisors is an integer number (4592700).

Almost surely, 2^138399272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138399272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146966400).

138399272 is an abundant number, since it is smaller than the sum of its proper divisors (155533528).

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

138399272 is a wasteful number, since it uses less digits than its factorization.

138399272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 578 (or 574 counting only the distinct ones).

The product of its digits is 163296, while the sum is 44.

The square root of 138399272 is about 11764.3219949133. The cubic root of 138399272 is about 517.2628264317.

The spelling of 138399272 in words is "one hundred thirty-eight million, three hundred ninety-nine thousand, two hundred seventy-two".