33528721 has 2 divisors, whose sum is σ = 33528722. Its totient is φ = 33528720.

The previous prime is 33528707. The next prime is 33528731. The reversal of 33528721 is 12782533.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28515600 + 5013121 = 5340^2 + 2239^2 .

It is a cyclic number.

It is not a de Polignac number, because 33528721 - 2⁵ = 33528689 is a prime.

It is a super-2 number, since 2×33528721² = 2248350263791682, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (33528731) 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, 16764360 + 16764361.

It is an arithmetic number, because the mean of its divisors is an integer number (16764361).

Almost surely, 2^33528721 is an apocalyptic number.

It is an amenable number.

33528721 is a deficient number, since it is larger than the sum of its proper divisors (1).

33528721 is an equidigital number, since it uses as much as digits as its factorization.

33528721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 31.

The square root of 33528721 is about 5790.3990363359. The cubic root of 33528721 is about 322.4573859524.

The spelling of 33528721 in words is "thirty-three million, five hundred twenty-eight thousand, seven hundred twenty-one".