33505981 has 2 divisors, whose sum is σ = 33505982. Its totient is φ = 33505980.

The previous prime is 33505961. The next prime is 33505993. The reversal of 33505981 is 18950533.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22714756 + 10791225 = 4766^2 + 3285^2 .

It is a cyclic number.

It is not a de Polignac number, because 33505981 - 2⁷ = 33505853 is a prime.

It is a super-2 number, since 2×33505981² = 2245301525544722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33505951) 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, 16752990 + 16752991.

It is an arithmetic number, because the mean of its divisors is an integer number (16752991).

Almost surely, 2^33505981 is an apocalyptic number.

It is an amenable number.

33505981 is a deficient number, since it is larger than the sum of its proper divisors (1).

33505981 is an equidigital number, since it uses as much as digits as its factorization.

33505981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 34.

The square root of 33505981 is about 5788.4351080409. The cubic root of 33505981 is about 322.3844699658.

The spelling of 33505981 in words is "thirty-three million, five hundred five thousand, nine hundred eighty-one".