138144220 has 12 divisors (see below), whose sum is σ = 290102904. Its totient is φ = 55257680.

The previous prime is 138144217. The next prime is 138144229. The reversal of 138144220 is 22441831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138144229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3453586 + ... + 3453625.

It is an arithmetic number, because the mean of its divisors is an integer number (24175242).

Almost surely, 2^138144220 is an apocalyptic number.

138144220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138144220 is an abundant number, since it is smaller than the sum of its proper divisors (151958684).

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

138144220 is a wasteful number, since it uses less digits than its factorization.

138144220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6907220 (or 6907218 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 138144220 is about 11753.4769323805. The cubic root of 138144220 is about 516.9448814930.

The spelling of 138144220 in words is "one hundred thirty-eight million, one hundred forty-four thousand, two hundred twenty".