22717021 has 4 divisors (see below), whose sum is σ = 22942044. Its totient is φ = 22492000.

The previous prime is 22717007. The next prime is 22717033. The reversal of 22717021 is 12071722.

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 18369796 + 4347225 = 4286^2 + 2085^2 .

It is a cyclic number.

It is not a de Polignac number, because 22717021 - 2¹⁹ = 22192733 is a prime.

It is a super-2 number, since 2×22717021² = 1032126086228882, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) 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 a junction number, because it is equal to n+sod(n) for n = 22716983 and 22717001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22717061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112360 + ... + 112561.

It is an arithmetic number, because the mean of its divisors is an integer number (5735511).

Almost surely, 2^22717021 is an apocalyptic number.

It is an amenable number.

22717021 is a deficient number, since it is larger than the sum of its proper divisors (225023).

22717021 is a wasteful number, since it uses less digits than its factorization.

22717021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225022.

The product of its (nonzero) digits is 392, while the sum is 22.

The square root of 22717021 is about 4766.2376147230. The cubic root of 22717021 is about 283.2155707455.

Adding to 22717021 its reverse (12071722), we get a palindrome (34788743).

The spelling of 22717021 in words is "twenty-two million, seven hundred seventeen thousand, twenty-one".