231218856 has 96 divisors (see below), whose sum is σ = 706773600. Its totient is φ = 67643520.

The previous prime is 231218851. The next prime is 231218857. The reversal of 231218856 is 658812132.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 231218856.

It is not an unprimeable number, because it can be changed into a prime (231218851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17935 + ... + 28001.

It is an arithmetic number, because the mean of its divisors is an integer number (7362225).

Almost surely, 2^231218856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231218856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (353386800).

231218856 is an abundant number, since it is smaller than the sum of its proper divisors (475554744).

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

231218856 is a wasteful number, since it uses less digits than its factorization.

231218856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10119 (or 10112 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 231218856 is about 15205.8822828536. The cubic root of 231218856 is about 613.7729569715.

The spelling of 231218856 in words is "two hundred thirty-one million, two hundred eighteen thousand, eight hundred fifty-six".