231220 has 24 divisors (see below), whose sum is σ = 530208. Its totient is φ = 84000.

The previous prime is 231197. The next prime is 231223. The reversal of 231220 is 22132.

231220 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 231197 and 231206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231223) by changing a digit.

231220 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 306 + ... + 745.

It is an arithmetic number, because the mean of its divisors is an integer number (22092).

2²³¹²²⁰ is an apocalyptic number.

231220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231220 is an abundant number, since it is smaller than the sum of its proper divisors (298988).

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

231220 is a wasteful number, since it uses less digits than its factorization.

231220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071 (or 1069 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 231220 is about 480.8534080154. The cubic root of 231220 is about 61.3773969223.

Adding to 231220 its reverse (22132), we get a palindrome (253352).

It can be divided in two parts, 2312 and 20, that added together give a palindrome (2332).

The spelling of 231220 in words is "two hundred thirty-one thousand, two hundred twenty".