22728665 has 4 divisors (see below), whose sum is σ = 27274404. Its totient is φ = 18182928.

The previous prime is 22728659. The next prime is 22728689. The reversal of 22728665 is 56682722.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16297369 + 6431296 = 4037^2 + 2536^2 .

It is a cyclic number.

It is not a de Polignac number, because 22728665 - 2¹⁴ = 22712281 is a prime.

It is a Duffinian number.

It is a Curzon 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, 2272862 + ... + 2272871.

It is an arithmetic number, because the mean of its divisors is an integer number (6818601).

Almost surely, 2^22728665 is an apocalyptic number.

It is an amenable number.

22728665 is a deficient number, since it is larger than the sum of its proper divisors (4545739).

22728665 is an equidigital number, since it uses as much as digits as its factorization.

22728665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4545738.

The product of its digits is 80640, while the sum is 38.

The square root of 22728665 is about 4767.4589667872. The cubic root of 22728665 is about 283.2639514850.

The spelling of 22728665 in words is "twenty-two million, seven hundred twenty-eight thousand, six hundred sixty-five".