33021221 has 4 divisors (see below), whose sum is σ = 34759200. Its totient is φ = 31283244.

The previous prime is 33021217. The next prime is 33021239. The reversal of 33021221 is 12212033.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 33021221 - 2² = 33021217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 33021196 and 33021205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33021211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 868961 + ... + 868998.

It is an arithmetic number, because the mean of its divisors is an integer number (8689800).

Almost surely, 2^33021221 is an apocalyptic number.

It is an amenable number.

33021221 is a deficient number, since it is larger than the sum of its proper divisors (1737979).

33021221 is a wasteful number, since it uses less digits than its factorization.

33021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1737978.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 33021221 is about 5746.4094006606. The cubic root of 33021221 is about 320.8221728994.

Adding to 33021221 its reverse (12212033), we get a palindrome (45233254).

The spelling of 33021221 in words is "thirty-three million, twenty-one thousand, two hundred twenty-one".