21855096 has 80 divisors (see below), whose sum is σ = 63379800. Its totient is φ = 7027776.

The previous prime is 21855089. The next prime is 21855121. The reversal of 21855096 is 69055812.

It is a happy number.

21855096 is a `hidden beast` number, since 2 + 18 + 550 + 96 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21855096.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18211 + ... + 19373.

Almost surely, 2^21855096 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 21855096, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31689900).

21855096 is an abundant number, since it is smaller than the sum of its proper divisors (41524704).

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

21855096 is a wasteful number, since it uses less digits than its factorization.

21855096 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1210 (or 1197 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 21855096 is about 4674.9434221175. The cubic root of 21855096 is about 279.5873854575.

The spelling of 21855096 in words is "twenty-one million, eight hundred fifty-five thousand, ninety-six".