221221033 has 6 divisors (see below), whose sum is σ = 243160442. Its totient is φ = 201109920.

The previous prime is 221220997. The next prime is 221221037. The reversal of 221221033 is 330122122.

221221033 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 208282624 + 12938409 = 14432^2 + 3597^2 .

It is a de Polignac number, because none of the positive numbers 2^k-221221033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221220998 and 221221016.

It is not an unprimeable number, because it can be changed into a prime (221221037) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 914016 + ... + 914257.

Almost surely, 2^221221033 is an apocalyptic number.

It is an amenable number.

221221033 is a deficient number, since it is larger than the sum of its proper divisors (21939409).

221221033 is a wasteful number, since it uses less digits than its factorization.

221221033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1828295 (or 1828284 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 221221033 is about 14873.5010337176. The cubic root of 221221033 is about 604.7958539875.

Adding to 221221033 its reverse (330122122), we get a palindrome (551343155).

The spelling of 221221033 in words is "two hundred twenty-one million, two hundred twenty-one thousand, thirty-three".