217228 has 12 divisors (see below), whose sum is σ = 414792. Its totient is φ = 98720.

The previous prime is 217223. The next prime is 217229. The reversal of 217228 is 822712.

217228 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an Ulam number.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 217199 and 217208.

It is not an unprimeable number, because it can be changed into a prime (217223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2425 + ... + 2512.

It is an arithmetic number, because the mean of its divisors is an integer number (34566).

2²¹⁷²²⁸ is an apocalyptic number.

It is an amenable number.

217228 is a deficient number, since it is larger than the sum of its proper divisors (197564).

217228 is a wasteful number, since it uses less digits than its factorization.

217228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4952 (or 4950 counting only the distinct ones).

The product of its digits is 448, while the sum is 22.

The square root of 217228 is about 466.0772468164. The cubic root of 217228 is about 60.1134889062.

The spelling of 217228 in words is "two hundred seventeen thousand, two hundred twenty-eight".