221964 has 24 divisors (see below), whose sum is σ = 529200. Its totient is φ = 72384.

The previous prime is 221957. The next prime is 221987. The reversal of 221964 is 469122.

221964 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a nialpdrome in base 12.

It is an unprimeable number.

221964 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 7 ways as a sum of consecutive naturals, for example, 462 + ... + 810.

It is an arithmetic number, because the mean of its divisors is an integer number (22050).

2²²¹⁹⁶⁴ is an apocalyptic number.

It is an amenable number.

221964 is an abundant number, since it is smaller than the sum of its proper divisors (307236).

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

221964 is a wasteful number, since it uses less digits than its factorization.

221964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 407 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 221964 is about 471.1305551543. The cubic root of 221964 is about 60.5472162887.

The spelling of 221964 in words is "two hundred twenty-one thousand, nine hundred sixty-four".