21105633399 has 8 divisors (see below), whose sum is σ = 29796188400. Its totient is φ = 13242750336.

The previous prime is 21105633383. The next prime is 21105633401. The reversal of 21105633399 is 99333650112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21105633399 - 2⁴ = 21105633383 is a prime.

It is a super-2 number, since 2×21105633399² (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 21105633399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21105633349) 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, 206917924 + ... + 206918025.

It is an arithmetic number, because the mean of its divisors is an integer number (3724523550).

Almost surely, 2^21105633399 is an apocalyptic number.

21105633399 is a deficient number, since it is larger than the sum of its proper divisors (8690555001).

21105633399 is a wasteful number, since it uses less digits than its factorization.

21105633399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413835969.

The product of its (nonzero) digits is 131220, while the sum is 42.

The spelling of 21105633399 in words is "twenty-one billion, one hundred five million, six hundred thirty-three thousand, three hundred ninety-nine".