221439985 has 16 divisors (see below), whose sum is σ = 286675200. Its totient is φ = 163235520.

The previous prime is 221439979. The next prime is 221439997. The reversal of 221439985 is 589934122.

It is not a de Polignac number, because 221439985 - 2²¹ = 219342833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38316 + ... + 43714.

It is an arithmetic number, because the mean of its divisors is an integer number (17917200).

Almost surely, 2^221439985 is an apocalyptic number.

It is an amenable number.

221439985 is a deficient number, since it is larger than the sum of its proper divisors (65235215).

221439985 is a wasteful number, since it uses less digits than its factorization.

221439985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6048.

The product of its digits is 155520, while the sum is 43.

The square root of 221439985 is about 14880.8596861875. The cubic root of 221439985 is about 604.9953190449.

The spelling of 221439985 in words is "two hundred twenty-one million, four hundred thirty-nine thousand, nine hundred eighty-five".