21859752 has 48 divisors (see below), whose sum is σ = 57313440. Its totient is φ = 6934752.

The previous prime is 21859751. The next prime is 21859753. The reversal of 21859752 is 25795812.

It is an interprime number because it is at equal distance from previous prime (21859751) and next prime (21859753).

It is a self number, because there is not a number n which added to its sum of digits gives 21859752.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21859751) 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, 109749 + ... + 109947.

It is an arithmetic number, because the mean of its divisors is an integer number (1194030).

Almost surely, 2^21859752 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21859752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28656720).

21859752 is an abundant number, since it is smaller than the sum of its proper divisors (35453688).

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

21859752 is a wasteful number, since it uses less digits than its factorization.

21859752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430 (or 227 counting only the distinct ones).

The product of its digits is 50400, while the sum is 39.

The square root of 21859752 is about 4675.4413695394. The cubic root of 21859752 is about 279.6072384388.

The spelling of 21859752 in words is "twenty-one million, eight hundred fifty-nine thousand, seven hundred fifty-two".