20307223 has 4 divisors (see below), whose sum is σ = 20779528. Its totient is φ = 19834920.

The previous prime is 20307179. The next prime is 20307233. The reversal of 20307223 is 32270302.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20307223 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20307223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20307233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 236088 + ... + 236173.

It is an arithmetic number, because the mean of its divisors is an integer number (5194882).

Almost surely, 2^20307223 is an apocalyptic number.

20307223 is a deficient number, since it is larger than the sum of its proper divisors (472305).

20307223 is an equidigital number, since it uses as much as digits as its factorization.

20307223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472304.

The product of its (nonzero) digits is 504, while the sum is 19.

The square root of 20307223 is about 4506.3536257156. The cubic root of 20307223 is about 272.8245909025.

Adding to 20307223 its reverse (32270302), we get a palindrome (52577525).

The spelling of 20307223 in words is "twenty million, three hundred seven thousand, two hundred twenty-three".