21744787272 has 128 divisors (see below), whose sum is σ = 61756800000. Its totient is φ = 6324998400.

The previous prime is 21744787247. The next prime is 21744787283. The reversal of 21744787272 is 27278744712.

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, 2954397 + ... + 2961747.

It is an arithmetic number, because the mean of its divisors is an integer number (482475000).

Almost surely, 2^21744787272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21744787272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30878400000).

21744787272 is an abundant number, since it is smaller than the sum of its proper divisors (40012012728).

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

21744787272 is a wasteful number, since it uses less digits than its factorization.

21744787272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7891 (or 7887 counting only the distinct ones).

The product of its digits is 2458624, while the sum is 51.

The spelling of 21744787272 in words is "twenty-one billion, seven hundred forty-four million, seven hundred eighty-seven thousand, two hundred seventy-two".