231445220 has 12 divisors (see below), whose sum is σ = 486035004. Its totient is φ = 92578080.

The previous prime is 231445217. The next prime is 231445241. The reversal of 231445220 is 22544132.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 76492516 + 154952704 = 8746^2 + 12448^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5786111 + ... + 5786150.

It is an arithmetic number, because the mean of its divisors is an integer number (40502917).

Almost surely, 2^231445220 is an apocalyptic number.

231445220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231445220 is an abundant number, since it is smaller than the sum of its proper divisors (254589784).

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

231445220 is a wasteful number, since it uses less digits than its factorization.

231445220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11572270 (or 11572268 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 231445220 is about 15213.3237656996. The cubic root of 231445220 is about 613.9731868735.

Adding to 231445220 its reverse (22544132), we get a palindrome (253989352).

The spelling of 231445220 in words is "two hundred thirty-one million, four hundred forty-five thousand, two hundred twenty".