21885018944 has 28 divisors (see below), whose sum is σ = 43875809124. Its totient is φ = 10829697024.

The previous prime is 21885018937. The next prime is 21885018971. The reversal of 21885018944 is 44981058812.

It can be written as a sum of positive squares in 2 ways, for example, as 11092302400 + 10792716544 = 105320^2 + 103888^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21885018892 and 21885018901.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1756439 + ... + 1768854.

It is an arithmetic number, because the mean of its divisors is an integer number (1566993183).

Almost surely, 2^21885018944 is an apocalyptic number.

It is an amenable number.

21885018944 is an abundant number, since it is smaller than the sum of its proper divisors (21990790180).

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

21885018944 is an equidigital number, since it uses as much as digits as its factorization.

21885018944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3525402 (or 3525392 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 50.

The spelling of 21885018944 in words is "twenty-one billion, eight hundred eighty-five million, eighteen thousand, nine hundred forty-four".