21633369 has 16 divisors (see below), whose sum is σ = 29390592. Its totient is φ = 14151888.

The previous prime is 21633349. The next prime is 21633371. The reversal of 21633369 is 96333612.

It is not a de Polignac number, because 21633369 - 2¹¹ = 21631321 is a prime.

It is a super-2 number, since 2×21633369² = 936005308580322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21633329) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 70314 + ... + 70620.

It is an arithmetic number, because the mean of its divisors is an integer number (1836912).

Almost surely, 2^21633369 is an apocalyptic number.

It is an amenable number.

21633369 is a deficient number, since it is larger than the sum of its proper divisors (7757223).

21633369 is a wasteful number, since it uses less digits than its factorization.

21633369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676.

The product of its digits is 17496, while the sum is 33.

The square root of 21633369 is about 4651.1685628453. The cubic root of 21633369 is about 278.6386684311.

The spelling of 21633369 in words is "twenty-one million, six hundred thirty-three thousand, three hundred sixty-nine".