22207721 has 8 divisors (see below), whose sum is σ = 22730688. Its totient is φ = 21690000.

The previous prime is 22207709. The next prime is 22207723. The reversal of 22207721 is 12770222.

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

It is a cyclic number.

It is not a de Polignac number, because 22207721 - 2⁶ = 22207657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22207723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8006 + ... + 10416.

It is an arithmetic number, because the mean of its divisors is an integer number (2841336).

Almost surely, 2^22207721 is an apocalyptic number.

It is an amenable number.

22207721 is a deficient number, since it is larger than the sum of its proper divisors (522967).

22207721 is a wasteful number, since it uses less digits than its factorization.

22207721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2623.

The product of its (nonzero) digits is 784, while the sum is 23.

The square root of 22207721 is about 4712.5068700215. The cubic root of 22207721 is about 281.0830544378.

Adding to 22207721 its reverse (12770222), we get a palindrome (34977943).

The spelling of 22207721 in words is "twenty-two million, two hundred seven thousand, seven hundred twenty-one".