221968 has 10 divisors (see below), whose sum is σ = 430094. Its totient is φ = 110976.

The previous prime is 221957. The next prime is 221987. The reversal of 221968 is 869122.

It is a happy number.

221968 is nontrivially palindromic in base 6.

It can be written as a sum of positive squares in only one way, i.e., 186624 + 35344 = 432^2 + 188^2 .

It is a nialpdrome in base 12.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 6921 + ... + 6952.

2²²¹⁹⁶⁸ is an apocalyptic number.

It is an amenable number.

221968 is a deficient number, since it is larger than the sum of its proper divisors (208126).

221968 is a wasteful number, since it uses less digits than its factorization.

221968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13881 (or 13875 counting only the distinct ones).

The product of its digits is 1728, while the sum is 28.

The square root of 221968 is about 471.1348002430. The cubic root of 221968 is about 60.5475799925.

The spelling of 221968 in words is "two hundred twenty-one thousand, nine hundred sixty-eight".