138222720 has 256 divisors, whose sum is σ = 516528000. Its totient is φ = 34836480.

The previous prime is 138222703. The next prime is 138222731. The reversal of 138222720 is 27222831.

It is a happy number.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 328110 + ... + 328530.

Almost surely, 2^138222720 is an apocalyptic number.

138222720 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 138222720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258264000).

138222720 is an abundant number, since it is smaller than the sum of its proper divisors (378305280).

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

138222720 is a wasteful number, since it uses less digits than its factorization.

138222720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 138222720 is about 11756.8158954710. The cubic root of 138222720 is about 517.0427803630.

The spelling of 138222720 in words is "one hundred thirty-eight million, two hundred twenty-two thousand, seven hundred twenty".