138231240 has 192 divisors, whose sum is σ = 490665600. Its totient is φ = 30514176.

The previous prime is 138231239. The next prime is 138231319. The reversal of 138231240 is 42132831.

138231240 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 (24).

It is a self number, because there is not a number n which added to its sum of digits gives 138231240.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1553116 + ... + 1553204.

It is an arithmetic number, because the mean of its divisors is an integer number (2555550).

Almost surely, 2^138231240 is an apocalyptic number.

138231240 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 138231240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (245332800).

138231240 is an abundant number, since it is smaller than the sum of its proper divisors (352434360).

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

138231240 is a wasteful number, since it uses less digits than its factorization.

138231240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 138231240 is about 11757.1782328924. The cubic root of 138231240 is about 517.0534035900.

The spelling of 138231240 in words is "one hundred thirty-eight million, two hundred thirty-one thousand, two hundred forty".