21652743944 has 32 divisors (see below), whose sum is σ = 43728890520. Its totient is φ = 9991973376.

The previous prime is 21652743911. The next prime is 21652743949. The reversal of 21652743944 is 44934725612.

It can be written as a sum of positive squares in 4 ways, for example, as 16734527044 + 4918216900 = 129362^2 + 70130^2 .

It is not an unprimeable number, because it can be changed into a prime (21652743949) 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, 852452 + ... + 877484.

Almost surely, 2^21652743944 is an apocalyptic number.

It is an amenable number.

21652743944 is an abundant number, since it is smaller than the sum of its proper divisors (22076146576).

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

21652743944 is a wasteful number, since it uses less digits than its factorization.

21652743944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33369 (or 33365 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 47.

The spelling of 21652743944 in words is "twenty-one billion, six hundred fifty-two million, seven hundred forty-three thousand, nine hundred forty-four".