221682 has 8 divisors (see below), whose sum is σ = 443376. Its totient is φ = 73892.

The previous prime is 221677. The next prime is 221707. The reversal of 221682 is 286122.

It is a sphenic number, since it is the product of 3 distinct primes.

221682 is an admirable number.

It is an unprimeable number.

221682 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, 18468 + ... + 18479.

It is an arithmetic number, because the mean of its divisors is an integer number (55422).

2²²¹⁶⁸² is an apocalyptic number.

221682 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

221682 is a wasteful number, since it uses less digits than its factorization.

221682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36952.

The product of its digits is 384, while the sum is 21.

The square root of 221682 is about 470.8311799361. The cubic root of 221682 is about 60.5215641546.

It can be divided in two parts, 221 and 682, that added together give a triangular number (903 = T₄₂).

The spelling of 221682 in words is "two hundred twenty-one thousand, six hundred eighty-two".