22437721 has 4 divisors (see below), whose sum is σ = 22453200. Its totient is φ = 22422244.

The previous prime is 22437713. The next prime is 22437731. The reversal of 22437721 is 12773422.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12773422 = 2 ⋅6386711.

It is a cyclic number.

It is not a de Polignac number, because 22437721 - 2³ = 22437713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22437721.

It is not an unprimeable number, because it can be changed into a prime (22437731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5311 + ... + 8548.

It is an arithmetic number, because the mean of its divisors is an integer number (5613300).

Almost surely, 2^22437721 is an apocalyptic number.

It is an amenable number.

22437721 is a deficient number, since it is larger than the sum of its proper divisors (15479).

22437721 is a wasteful number, since it uses less digits than its factorization.

22437721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15478.

The product of its digits is 4704, while the sum is 28.

The square root of 22437721 is about 4736.8471581844. The cubic root of 22437721 is about 282.0500933763.

The spelling of 22437721 in words is "twenty-two million, four hundred thirty-seven thousand, seven hundred twenty-one".