33500221 has 2 divisors, whose sum is σ = 33500222. Its totient is φ = 33500220.

The previous prime is 33500219. The next prime is 33500231. The reversal of 33500221 is 12200533.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30096196 + 3404025 = 5486^2 + 1845^2 .

It is an emirp because it is prime and its reverse (12200533) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 33500221 - 2¹ = 33500219 is a prime.

It is a super-2 number, since 2×33500221² = 2244529614097682, which contains 22 as substring.

Together with 33500219, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 33500195 and 33500204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33500231) 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 as a sum of consecutive naturals, namely, 16750110 + 16750111.

It is an arithmetic number, because the mean of its divisors is an integer number (16750111).

Almost surely, 2^33500221 is an apocalyptic number.

It is an amenable number.

33500221 is a deficient number, since it is larger than the sum of its proper divisors (1).

33500221 is an equidigital number, since it uses as much as digits as its factorization.

33500221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 33500221 is about 5787.9375428558. The cubic root of 33500221 is about 322.3659952447.

Adding to 33500221 its reverse (12200533), we get a palindrome (45700754).

The spelling of 33500221 in words is "thirty-three million, five hundred thousand, two hundred twenty-one".