21864722 has 8 divisors (see below), whose sum is σ = 35778672. Its totient is φ = 9938500.

The previous prime is 21864659. The next prime is 21864757. The reversal of 21864722 is 22746812.

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, 496904 + ... + 496947.

It is an arithmetic number, because the mean of its divisors is an integer number (4472334).

Almost surely, 2^21864722 is an apocalyptic number.

21864722 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21864722 is a deficient number, since it is larger than the sum of its proper divisors (13913950).

21864722 is a wasteful number, since it uses less digits than its factorization.

21864722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993864.

The product of its digits is 10752, while the sum is 32.

The square root of 21864722 is about 4675.9728399553. The cubic root of 21864722 is about 279.6284271920.

The spelling of 21864722 in words is "twenty-one million, eight hundred sixty-four thousand, seven hundred twenty-two".