221994685 has 16 divisors (see below), whose sum is σ = 293614272. Its totient is φ = 159782400.

The previous prime is 221994659. The next prime is 221994697. The reversal of 221994685 is 586499122.

It is not a de Polignac number, because 221994685 - 2⁷ = 221994557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15471 + ... + 26140.

It is an arithmetic number, because the mean of its divisors is an integer number (18350892).

Almost surely, 2^221994685 is an apocalyptic number.

It is an amenable number.

221994685 is a deficient number, since it is larger than the sum of its proper divisors (71619587).

221994685 is a wasteful number, since it uses less digits than its factorization.

221994685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41724.

The product of its digits is 311040, while the sum is 46.

The square root of 221994685 is about 14899.4860649621. The cubic root of 221994685 is about 605.5000623926.

The spelling of 221994685 in words is "two hundred twenty-one million, nine hundred ninety-four thousand, six hundred eighty-five".