21864022 has 8 divisors (see below), whose sum is σ = 34522200. Its totient is φ = 10356624.

The previous prime is 21864019. The next prime is 21864049. The reversal of 21864022 is 22046812.

It is a happy number.

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

It is a super-3 number, since 3×21864022³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

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, 287647 + ... + 287722.

It is an arithmetic number, because the mean of its divisors is an integer number (4315275).

Almost surely, 2^21864022 is an apocalyptic number.

21864022 is a deficient number, since it is larger than the sum of its proper divisors (12658178).

21864022 is a wasteful number, since it uses less digits than its factorization.

21864022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575390.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 21864022 is about 4675.8979886221. The cubic root of 21864022 is about 279.6254430549.

The spelling of 21864022 in words is "twenty-one million, eight hundred sixty-four thousand, twenty-two".