22128720 has 40 divisors (see below), whose sum is σ = 68599776. Its totient is φ = 5900928.

The previous prime is 22128683. The next prime is 22128721. The reversal of 22128720 is 2782122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22128721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45862 + ... + 46341.

Almost surely, 2^22128720 is an apocalyptic number.

22128720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22128720 is an abundant number, since it is smaller than the sum of its proper divisors (46471056).

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

22128720 is a wasteful number, since it uses less digits than its factorization.

22128720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92219 (or 92213 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 22128720 is about 4704.1173454751. The cubic root of 22128720 is about 280.7493532896.

The spelling of 22128720 in words is "twenty-two million, one hundred twenty-eight thousand, seven hundred twenty".