33440221 has 2 divisors, whose sum is σ = 33440222. Its totient is φ = 33440220.

The previous prime is 33440213. The next prime is 33440233. The reversal of 33440221 is 12204433.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32936121 + 504100 = 5739^2 + 710^2 .

It is an emirp because it is prime and its reverse (12204433) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 33440221 - 2³ = 33440213 is a prime.

It is a super-3 number, since 3×33440221³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33440291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16720110 + 16720111.

It is an arithmetic number, because the mean of its divisors is an integer number (16720111).

Almost surely, 2^33440221 is an apocalyptic number.

It is an amenable number.

33440221 is a deficient number, since it is larger than the sum of its proper divisors (1).

33440221 is an equidigital number, since it uses as much as digits as its factorization.

33440221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 33440221 is about 5782.7520265009. The cubic root of 33440221 is about 322.1734241909.

Adding to 33440221 its reverse (12204433), we get a palindrome (45644654).

The spelling of 33440221 in words is "thirty-three million, four hundred forty thousand, two hundred twenty-one".