138613220 has 12 divisors (see below), whose sum is σ = 291087804. Its totient is φ = 55445280.

The previous prime is 138613217. The next prime is 138613231. The reversal of 138613220 is 22316831.

It can be written as a sum of positive squares in 2 ways, for example, as 34409956 + 104203264 = 5866^2 + 10208^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 138613220.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3465311 + ... + 3465350.

It is an arithmetic number, because the mean of its divisors is an integer number (24257317).

Almost surely, 2^138613220 is an apocalyptic number.

138613220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138613220 is an abundant number, since it is smaller than the sum of its proper divisors (152474584).

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

138613220 is a wasteful number, since it uses less digits than its factorization.

138613220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6930670 (or 6930668 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 138613220 is about 11773.4115701440. The cubic root of 138613220 is about 517.5292304586.

The spelling of 138613220 in words is "one hundred thirty-eight million, six hundred thirteen thousand, two hundred twenty".