21823669 has 12 divisors (see below), whose sum is σ = 25500204. Its totient is φ = 18622464.

The previous prime is 21823663. The next prime is 21823679. The reversal of 21823669 is 96632812.

It can be written as a sum of positive squares in 2 ways, for example, as 17114769 + 4708900 = 4137^2 + 2170^2 .

It is not a de Polignac number, because 21823669 - 2⁷ = 21823541 is a prime.

It is a super-2 number, since 2×21823669² = 952545057243122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21823663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11727 + ... + 13459.

It is an arithmetic number, because the mean of its divisors is an integer number (2125017).

Almost surely, 2^21823669 is an apocalyptic number.

It is an amenable number.

21823669 is a deficient number, since it is larger than the sum of its proper divisors (3676535).

21823669 is a wasteful number, since it uses less digits than its factorization.

21823669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004 (or 1997 counting only the distinct ones).

The product of its digits is 31104, while the sum is 37.

The square root of 21823669 is about 4671.5809957658. The cubic root of 21823669 is about 279.4533082953.

The spelling of 21823669 in words is "twenty-one million, eight hundred twenty-three thousand, six hundred sixty-nine".