21643301936 has 20 divisors (see below), whose sum is σ = 44400597912. Its totient is φ = 10185083136.

The previous prime is 21643301909. The next prime is 21643301941. The reversal of 21643301936 is 63910334612.

It is a super-2 number, since 2×21643301936² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21643301936.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39785210 + ... + 39785753.

Almost surely, 2^21643301936 is an apocalyptic number.

It is an amenable number.

21643301936 is an abundant number, since it is smaller than the sum of its proper divisors (22757295976).

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

21643301936 is a wasteful number, since it uses less digits than its factorization.

21643301936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79570988 (or 79570982 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 38.

The spelling of 21643301936 in words is "twenty-one billion, six hundred forty-three million, three hundred one thousand, nine hundred thirty-six".