20722128 has 40 divisors (see below), whose sum is σ = 61180608. Its totient is φ = 5920512.

The previous prime is 20722123. The next prime is 20722129. The reversal of 20722128 is 82122702.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 20722098 and 20722107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20722123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30501 + ... + 31172.

Almost surely, 2^20722128 is an apocalyptic number.

20722128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20722128 is an abundant number, since it is smaller than the sum of its proper divisors (40458480).

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

20722128 is a wasteful number, since it uses less digits than its factorization.

20722128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61691 (or 61685 counting only the distinct ones).

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

The square root of 20722128 is about 4552.1564120755. The cubic root of 20722128 is about 274.6701411360.

The spelling of 20722128 in words is "twenty million, seven hundred twenty-two thousand, one hundred twenty-eight".