20305223 has 4 divisors (see below), whose sum is σ = 20418840. Its totient is φ = 20191608.

The previous prime is 20305213. The next prime is 20305231. The reversal of 20305223 is 32250302.

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-20305223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20305213) 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, 56540 + ... + 56897.

It is an arithmetic number, because the mean of its divisors is an integer number (5104710).

Almost surely, 2^20305223 is an apocalyptic number.

20305223 is a deficient number, since it is larger than the sum of its proper divisors (113617).

20305223 is a wasteful number, since it uses less digits than its factorization.

20305223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113616.

The product of its (nonzero) digits is 360, while the sum is 17.

The square root of 20305223 is about 4506.1317113462. The cubic root of 20305223 is about 272.8156340386.

Adding to 20305223 its reverse (32250302), we get a palindrome (52555525).

The spelling of 20305223 in words is "twenty million, three hundred five thousand, two hundred twenty-three".