22721045 has 4 divisors (see below), whose sum is σ = 27265260. Its totient is φ = 18176832.

The previous prime is 22721029. The next prime is 22721051. The reversal of 22721045 is 54012722.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54012722 = 2 ⋅27006361.

It can be written as a sum of positive squares in 2 ways, for example, as 5564881 + 17156164 = 2359^2 + 4142^2 .

It is a cyclic number.

It is not a de Polignac number, because 22721045 - 2⁴ = 22721029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 22721045.

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, 2272100 + ... + 2272109.

It is an arithmetic number, because the mean of its divisors is an integer number (6816315).

Almost surely, 2^22721045 is an apocalyptic number.

It is an amenable number.

22721045 is a deficient number, since it is larger than the sum of its proper divisors (4544215).

22721045 is an equidigital number, since it uses as much as digits as its factorization.

22721045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4544214.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 22721045 is about 4766.6597319297. The cubic root of 22721045 is about 283.2322923068.

Adding to 22721045 its reverse (54012722), we get a palindrome (76733767).

The spelling of 22721045 in words is "twenty-two million, seven hundred twenty-one thousand, forty-five".