231332220 has 192 divisors, whose sum is σ = 866073600. Its totient is φ = 50077440.

The previous prime is 231332197. The next prime is 231332237. The reversal of 231332220 is 22233132.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 231332193 and 231332202.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 70210 + ... + 73430.

It is an arithmetic number, because the mean of its divisors is an integer number (4510800).

Almost surely, 2^231332220 is an apocalyptic number.

231332220 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 231332220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (433036800).

231332220 is an abundant number, since it is smaller than the sum of its proper divisors (634741380).

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

231332220 is a wasteful number, since it uses less digits than its factorization.

231332220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3265 (or 3257 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

The square root of 231332220 is about 15209.6094624418. The cubic root of 231332220 is about 613.8732492378.

Adding to 231332220 its reverse (22233132), we get a palindrome (253565352).

The spelling of 231332220 in words is "two hundred thirty-one million, three hundred thirty-two thousand, two hundred twenty".