33133221 has 24 divisors (see below), whose sum is σ = 55283904. Its totient is φ = 18898560.

The previous prime is 33133193. The next prime is 33133231. The reversal of 33133221 is 12233133.

33133221 is a `hidden beast` number, since 331 + 332 + 2 + 1 = 666.

It is not a de Polignac number, because 33133221 - 2⁹ = 33132709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 33133194 and 33133203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33133231) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8161 + ... + 11526.

It is an arithmetic number, because the mean of its divisors is an integer number (2303496).

Almost surely, 2^33133221 is an apocalyptic number.

It is an amenable number.

33133221 is a deficient number, since it is larger than the sum of its proper divisors (22150683).

33133221 is a wasteful number, since it uses less digits than its factorization.

33133221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19721 (or 19718 counting only the distinct ones).

The product of its digits is 324, while the sum is 18.

The square root of 33133221 is about 5756.1463671453. The cubic root of 33133221 is about 321.1844806754.

Adding to 33133221 its reverse (12233133), we get a palindrome (45366354).

The spelling of 33133221 in words is "thirty-three million, one hundred thirty-three thousand, two hundred twenty-one".