20408223 has 32 divisors (see below), whose sum is σ = 31622400. Its totient is φ = 11674080.

The previous prime is 20408191. The next prime is 20408231. The reversal of 20408223 is 32280402.

It is not a de Polignac number, because 20408223 - 2⁵ = 20408191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20408223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20408243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 75733 + ... + 76001.

It is an arithmetic number, because the mean of its divisors is an integer number (988200).

Almost surely, 2^20408223 is an apocalyptic number.

20408223 is a deficient number, since it is larger than the sum of its proper divisors (11214177).

20408223 is a wasteful number, since it uses less digits than its factorization.

20408223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324 (or 302 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 20408223 is about 4517.5461259405. The cubic root of 20408223 is about 273.2761498791.

Adding to 20408223 its reverse (32280402), we get a palindrome (52688625).

The spelling of 20408223 in words is "twenty million, four hundred eight thousand, two hundred twenty-three".