217628 has 12 divisors (see below), whose sum is σ = 390432. Its totient is φ = 106080.

The previous prime is 217619. The next prime is 217643. The reversal of 217628 is 826712.

217628 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 217597 and 217606.

It is a congruent number.

It is an unprimeable number.

217628 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 500 + ... + 827.

It is an arithmetic number, because the mean of its divisors is an integer number (32536).

2²¹⁷⁶²⁸ is an apocalyptic number.

It is an amenable number.

217628 is a deficient number, since it is larger than the sum of its proper divisors (172804).

217628 is a wasteful number, since it uses less digits than its factorization.

217628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1372 (or 1370 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 217628 is about 466.5061628746. The cubic root of 217628 is about 60.1503636057.

The spelling of 217628 in words is "two hundred seventeen thousand, six hundred twenty-eight".