21632643472 has 20 divisors (see below), whose sum is σ = 45723542256. Its totient is φ = 9833019680.

The previous prime is 21632643469. The next prime is 21632643511. The reversal of 21632643472 is 27434623612.

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, 61456198 + ... + 61456549.

Almost surely, 2^21632643472 is an apocalyptic number.

21632643472 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21632643472 is an abundant number, since it is smaller than the sum of its proper divisors (24090898784).

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

21632643472 is a wasteful number, since it uses less digits than its factorization.

21632643472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122912766 (or 122912760 counting only the distinct ones).

The product of its digits is 290304, while the sum is 40.

The spelling of 21632643472 in words is "twenty-one billion, six hundred thirty-two million, six hundred forty-three thousand, four hundred seventy-two".