21633255612 has 18 divisors (see below), whose sum is σ = 54684062888. Its totient is φ = 7211085192.

The previous prime is 21633255593. The next prime is 21633255617. The reversal of 21633255612 is 21655233612.

21633255612 is a `hidden beast` number, since 2 + 1 + 6 + 3 + 32 + 5 + 5 + 612 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 600923767 = 21633255612 / (2 + 1 + 6 + 3 + 3 + 2 + 5 + 5 + 6 + 1 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21633255617) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 300461848 + ... + 300461919.

Almost surely, 2^21633255612 is an apocalyptic number.

It is an amenable number.

21633255612 is an abundant number, since it is smaller than the sum of its proper divisors (33050807276).

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

21633255612 is a wasteful number, since it uses less digits than its factorization.

21633255612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600923777 (or 600923772 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The spelling of 21633255612 in words is "twenty-one billion, six hundred thirty-three million, two hundred fifty-five thousand, six hundred twelve".