21823828 has 24 divisors (see below), whose sum is σ = 41302688. Its totient is φ = 10030176.

The previous prime is 21823811. The next prime is 21823847. The reversal of 21823828 is 82832812.

It is a junction number, because it is equal to n+sod(n) for n = 21823793 and 21823802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13975 + ... + 15457.

Almost surely, 2^21823828 is an apocalyptic number.

It is an amenable number.

21823828 is a deficient number, since it is larger than the sum of its proper divisors (19478860).

21823828 is a wasteful number, since it uses less digits than its factorization.

21823828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783 (or 1781 counting only the distinct ones).

The product of its digits is 12288, while the sum is 34.

The square root of 21823828 is about 4671.5980135281. The cubic root of 21823828 is about 279.4539869617.

The spelling of 21823828 in words is "twenty-one million, eight hundred twenty-three thousand, eight hundred twenty-eight".