138220320 has 192 divisors, whose sum is σ = 514031616. Its totient is φ = 30551040.

The previous prime is 138220301. The next prime is 138220321. The reversal of 138220320 is 23022831.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (138220321) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 103497 + ... + 104823.

It is an arithmetic number, because the mean of its divisors is an integer number (2677248).

Almost surely, 2^138220320 is an apocalyptic number.

138220320 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 138220320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (257015808).

138220320 is an abundant number, since it is smaller than the sum of its proper divisors (375811296).

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

138220320 is a wasteful number, since it uses less digits than its factorization.

138220320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1383 (or 1375 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 138220320 is about 11756.7138265759. The cubic root of 138220320 is about 517.0397878259.

The spelling of 138220320 in words is "one hundred thirty-eight million, two hundred twenty thousand, three hundred twenty".