231228 has 24 divisors (see below), whose sum is σ = 599760. Its totient is φ = 77040.

The previous prime is 231223. The next prime is 231241. The reversal of 231228 is 822132.

It is a happy number.

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

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 231228.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231223) 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, 963 + ... + 1178.

It is an arithmetic number, because the mean of its divisors is an integer number (24990).

2²³¹²²⁸ is an apocalyptic number.

It is an amenable number.

231228 is an abundant number, since it is smaller than the sum of its proper divisors (368532).

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

231228 is a wasteful number, since it uses less digits than its factorization.

231228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2154 (or 2146 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 231228 is about 480.8617264869. The cubic root of 231228 is about 61.3781047814.

The spelling of 231228 in words is "two hundred thirty-one thousand, two hundred twenty-eight".