22443721 has 16 divisors (see below), whose sum is σ = 24076800. Its totient is φ = 20885760.

The previous prime is 22443713. The next prime is 22443749. The reversal of 22443721 is 12734422.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 22443721 - 2³ = 22443713 is a prime.

It is a super-2 number, since 2×22443721² = 1007441224651682, which contains 22 as substring.

It is a Duffinian number.

Its product of digits (2688) is a multiple of the sum of its prime divisors (336).

It is not an unprimeable number, because it can be changed into a prime (22443121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 150555 + ... + 150703.

It is an arithmetic number, because the mean of its divisors is an integer number (1504800).

Almost surely, 2^22443721 is an apocalyptic number.

It is an amenable number.

22443721 is a deficient number, since it is larger than the sum of its proper divisors (1633079).

22443721 is a wasteful number, since it uses less digits than its factorization.

22443721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336.

The product of its digits is 2688, while the sum is 25.

The square root of 22443721 is about 4737.4804485085. The cubic root of 22443721 is about 282.0752318435.

The spelling of 22443721 in words is "twenty-two million, four hundred forty-three thousand, seven hundred twenty-one".