21823000 has 64 divisors (see below), whose sum is σ = 51760800. Its totient is φ = 8611200.

The previous prime is 21822991. The next prime is 21823027. The reversal of 21823000 is 32812.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 138922 + ... + 139078.

Almost surely, 2^21823000 is an apocalyptic number.

21823000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21823000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25880400).

21823000 is an abundant number, since it is smaller than the sum of its proper divisors (29937800).

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

21823000 is a wasteful number, since it uses less digits than its factorization.

21823000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 21823000 is about 4671.5093920488. The cubic root of 21823000 is about 279.4504527386.

Adding to 21823000 its reverse (32812), we get a palindrome (21855812).

The spelling of 21823000 in words is "twenty-one million, eight hundred twenty-three thousand".