217569228 has 48 divisors (see below), whose sum is σ = 540865920. Its totient is φ = 67872384.

The previous prime is 217569227. The next prime is 217569241. The reversal of 217569228 is 822965712.

It is a self number, because there is not a number n which added to its sum of digits gives 217569228.

It is not an unprimeable number, because it can be changed into a prime (217569221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13176 + ... + 24672.

It is an arithmetic number, because the mean of its divisors is an integer number (11268040).

Almost surely, 2^217569228 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 217569228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (270432960).

217569228 is an abundant number, since it is smaller than the sum of its proper divisors (323296692).

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

217569228 is a wasteful number, since it uses less digits than its factorization.

217569228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11606 (or 11604 counting only the distinct ones).

The product of its digits is 120960, while the sum is 42.

The square root of 217569228 is about 14750.2280660334. The cubic root of 217569228 is about 601.4494843941.

The spelling of 217569228 in words is "two hundred seventeen million, five hundred sixty-nine thousand, two hundred twenty-eight".