21852660 has 96 divisors (see below), whose sum is σ = 66729600. Its totient is φ = 5322240.

The previous prime is 21852659. The next prime is 21852661. The reversal of 21852660 is 6625812.

It is an interprime number because it is at equal distance from previous prime (21852659) and next prime (21852661).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21852661) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32730 + ... + 33390.

It is an arithmetic number, because the mean of its divisors is an integer number (695100).

Almost surely, 2^21852660 is an apocalyptic number.

21852660 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 21852660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33364800).

21852660 is an abundant number, since it is smaller than the sum of its proper divisors (44876940).

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

21852660 is a wasteful number, since it uses less digits than its factorization.

21852660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721 (or 719 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 21852660 is about 4674.6828769447. The cubic root of 21852660 is about 279.5769973360.

The spelling of 21852660 in words is "twenty-one million, eight hundred fifty-two thousand, six hundred sixty".