21853230 has 64 divisors (see below), whose sum is σ = 63106560. Its totient is φ = 4731264.

The previous prime is 21853229. The next prime is 21853231. The reversal of 21853230 is 3235812.

It is an interprime number because it is at equal distance from previous prime (21853229) and next prime (21853231).

It is a super-2 number, since 2×21853230² = 955127322865800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21853230.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21853231) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1252 + ... + 6728.

It is an arithmetic number, because the mean of its divisors is an integer number (986040).

Almost surely, 2^21853230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21853230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31553280).

21853230 is an abundant number, since it is smaller than the sum of its proper divisors (41253330).

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

21853230 is a wasteful number, since it uses less digits than its factorization.

21853230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5513.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 21853230 is about 4674.7438432496. The cubic root of 21853230 is about 279.5794281233.

The spelling of 21853230 in words is "twenty-one million, eight hundred fifty-three thousand, two hundred thirty".