221020216 has 16 divisors (see below), whose sum is σ = 414671400. Its totient is φ = 110441184.

The previous prime is 221020211. The next prime is 221020237. The reversal of 221020216 is 612020122.

It is a self number, because there is not a number n which added to its sum of digits gives 221020216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221020211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6591 + ... + 22033.

Almost surely, 2^221020216 is an apocalyptic number.

It is an amenable number.

221020216 is a deficient number, since it is larger than the sum of its proper divisors (193651184).

221020216 is a wasteful number, since it uses less digits than its factorization.

221020216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17238 (or 17234 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 221020216 is about 14866.7486694300. The cubic root of 221020216 is about 604.6127941516.

Adding to 221020216 its reverse (612020122), we get a palindrome (833040338).

The spelling of 221020216 in words is "two hundred twenty-one million, twenty thousand, two hundred sixteen".