20423320 has 16 divisors (see below), whose sum is σ = 45952560. Its totient is φ = 8169312.

The previous prime is 20423257. The next prime is 20423329. The reversal of 20423320 is 2332402.

It is a super-2 number, since 2×20423320² = 834223999644800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20423294 and 20423303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20423329) 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, 255252 + ... + 255331.

It is an arithmetic number, because the mean of its divisors is an integer number (2872035).

Almost surely, 2^20423320 is an apocalyptic number.

20423320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20423320 is an abundant number, since it is smaller than the sum of its proper divisors (25529240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20423320 is a wasteful number, since it uses less digits than its factorization.

20423320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510594 (or 510590 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 16.

The square root of 20423320 is about 4519.2167462958. The cubic root of 20423320 is about 273.3435186898.

Adding to 20423320 its reverse (2332402), we get a palindrome (22755722).

The spelling of 20423320 in words is "twenty million, four hundred twenty-three thousand, three hundred twenty".