231013220 has 24 divisors (see below), whose sum is σ = 494283384. Its totient is φ = 90661376.

The previous prime is 231013199. The next prime is 231013247. The reversal of 231013220 is 22310132.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4631104 + 226382116 = 2152^2 + 15046^2 .

It is a junction number, because it is equal to n+sod(n) for n = 231013195 and 231013204.

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, 107909 + ... + 110028.

It is an arithmetic number, because the mean of its divisors is an integer number (20595141).

Almost surely, 2^231013220 is an apocalyptic number.

231013220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231013220 is an abundant number, since it is smaller than the sum of its proper divisors (263270164).

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

231013220 is a wasteful number, since it uses less digits than its factorization.

231013220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217999 (or 217997 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 231013220 is about 15199.1190534189. The cubic root of 231013220 is about 613.5909486745.

Adding to 231013220 its reverse (22310132), we get a palindrome (253323352).

The spelling of 231013220 in words is "two hundred thirty-one million, thirteen thousand, two hundred twenty".