22021573728 has 288 divisors, whose sum is σ = 73741788288. Its totient is φ = 5689958400.

The previous prime is 22021573711. The next prime is 22021573733. The reversal of 22021573728 is 82737512022.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10916976 + ... + 10918992.

It is an arithmetic number, because the mean of its divisors is an integer number (256047876).

Almost surely, 2^22021573728 is an apocalyptic number.

22021573728 is a gapful number since it is divisible by the number (28) 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 22021573728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36870894144).

22021573728 is an abundant number, since it is smaller than the sum of its proper divisors (51720214560).

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

22021573728 is a wasteful number, since it uses less digits than its factorization.

22021573728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2266 (or 2251 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 39.

The spelling of 22021573728 in words is "twenty-two billion, twenty-one million, five hundred seventy-three thousand, seven hundred twenty-eight".