33066721 has 2 divisors, whose sum is σ = 33066722. Its totient is φ = 33066720.

The previous prime is 33066713. The next prime is 33066743. The reversal of 33066721 is 12766033.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28740321 + 4326400 = 5361^2 + 2080^2 .

It is a cyclic number.

It is not a de Polignac number, because 33066721 - 2³ = 33066713 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 33066721.

It is not a weakly prime, because it can be changed into another prime (33066791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16533360 + 16533361.

It is an arithmetic number, because the mean of its divisors is an integer number (16533361).

Almost surely, 2^33066721 is an apocalyptic number.

It is an amenable number.

33066721 is a deficient number, since it is larger than the sum of its proper divisors (1).

33066721 is an equidigital number, since it uses as much as digits as its factorization.

33066721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 28.

The square root of 33066721 is about 5750.3670317641. The cubic root of 33066721 is about 320.9694590884.

The spelling of 33066721 in words is "thirty-three million, sixty-six thousand, seven hundred twenty-one".