23031220 has 24 divisors (see below), whose sum is σ = 50034600. Its totient is φ = 8894592.

The previous prime is 23031167. The next prime is 23031227. The reversal of 23031220 is 2213032.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6822544 + 16208676 = 2612^2 + 4026^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 23031220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23031227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19275 + ... + 20434.

It is an arithmetic number, because the mean of its divisors is an integer number (2084775).

Almost surely, 2^23031220 is an apocalyptic number.

23031220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23031220 is an abundant number, since it is smaller than the sum of its proper divisors (27003380).

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

23031220 is a wasteful number, since it uses less digits than its factorization.

23031220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39747 (or 39745 counting only the distinct ones).

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

The square root of 23031220 is about 4799.0853295185. The cubic root of 23031220 is about 284.5153144854.

Adding to 23031220 its reverse (2213032), we get a palindrome (25244252).

The spelling of 23031220 in words is "twenty-three million, thirty-one thousand, two hundred twenty".