20312320 has 72 divisors (see below), whose sum is σ = 55629504. Its totient is φ = 6961152.

The previous prime is 20312309. The next prime is 20312351. The reversal of 20312320 is 2321302.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20312320.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7827 + ... + 10093.

It is an arithmetic number, because the mean of its divisors is an integer number (772632).

Almost surely, 2^20312320 is an apocalyptic number.

20312320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20312320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27814752).

20312320 is an abundant number, since it is smaller than the sum of its proper divisors (35317184).

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

20312320 is an equidigital number, since it uses as much as digits as its factorization.

20312320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2295 (or 2281 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 20312320 is about 4506.9191250787. The cubic root of 20312320 is about 272.8474148112.

Adding to 20312320 its reverse (2321302), we get a palindrome (22633622).

The spelling of 20312320 in words is "twenty million, three hundred twelve thousand, three hundred twenty".