221649616 has 10 divisors (see below), whose sum is σ = 429446162. Its totient is φ = 110824800.

The previous prime is 221649599. The next prime is 221649619. The reversal of 221649616 is 616946122.

It can be written as a sum of positive squares in only one way, i.e., 132158016 + 89491600 = 11496^2 + 9460^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221649619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6926535 + ... + 6926566.

Almost surely, 2^221649616 is an apocalyptic number.

It is an amenable number.

221649616 is a deficient number, since it is larger than the sum of its proper divisors (207796546).

221649616 is a wasteful number, since it uses less digits than its factorization.

221649616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13853109 (or 13853103 counting only the distinct ones).

The product of its digits is 31104, while the sum is 37.

The square root of 221649616 is about 14887.9016654463. The cubic root of 221649616 is about 605.1861695124.

The spelling of 221649616 in words is "two hundred twenty-one million, six hundred forty-nine thousand, six hundred sixteen".