22170865 has 4 divisors (see below), whose sum is σ = 26605044. Its totient is φ = 17736688.

The previous prime is 22170851. The next prime is 22170931. The reversal of 22170865 is 56807122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56807122 = 2 ⋅28403561.

It can be written as a sum of positive squares in 2 ways, for example, as 13667809 + 8503056 = 3697^2 + 2916^2 .

It is a cyclic number.

It is not a de Polignac number, because 22170865 - 2⁹ = 22170353 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian 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, 2217082 + ... + 2217091.

It is an arithmetic number, because the mean of its divisors is an integer number (6651261).

Almost surely, 2^22170865 is an apocalyptic number.

It is an amenable number.

22170865 is a deficient number, since it is larger than the sum of its proper divisors (4434179).

22170865 is an equidigital number, since it uses as much as digits as its factorization.

22170865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4434178.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 22170865 is about 4708.5948009996. The cubic root of 22170865 is about 280.9274729130.

Adding to 22170865 its reverse (56807122), we get a palindrome (78977987).

The spelling of 22170865 in words is "twenty-two million, one hundred seventy thousand, eight hundred sixty-five".