138331220 has 12 divisors (see below), whose sum is σ = 290495604. Its totient is φ = 55332480.

The previous prime is 138331211. The next prime is 138331243. The reversal of 138331220 is 22133831.

It can be written as a sum of positive squares in 2 ways, for example, as 53027524 + 85303696 = 7282^2 + 9236^2 .

It is a congruent number.

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, 3458261 + ... + 3458300.

It is an arithmetic number, because the mean of its divisors is an integer number (24207967).

Almost surely, 2^138331220 is an apocalyptic number.

138331220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138331220 is an abundant number, since it is smaller than the sum of its proper divisors (152164384).

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

138331220 is a wasteful number, since it uses less digits than its factorization.

138331220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6916570 (or 6916568 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 138331220 is about 11761.4293349065. The cubic root of 138331220 is about 517.1780318119.

The spelling of 138331220 in words is "one hundred thirty-eight million, three hundred thirty-one thousand, two hundred twenty".