21855722 has 8 divisors (see below), whose sum is σ = 37466976. Its totient is φ = 9366732.

The previous prime is 21855709. The next prime is 21855737. The reversal of 21855722 is 22755812.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 780548 + ... + 780575.

It is an arithmetic number, because the mean of its divisors is an integer number (4683372).

Almost surely, 2^21855722 is an apocalyptic number.

21855722 is a deficient number, since it is larger than the sum of its proper divisors (15611254).

21855722 is a wasteful number, since it uses less digits than its factorization.

21855722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561132.

The product of its digits is 11200, while the sum is 32.

The square root of 21855722 is about 4675.0103743200. The cubic root of 21855722 is about 279.5900548583.

The spelling of 21855722 in words is "twenty-one million, eight hundred fifty-five thousand, seven hundred twenty-two".