33381661 has 2 divisors, whose sum is σ = 33381662. Its totient is φ = 33381660.

The previous prime is 33381641. The next prime is 33381683. The reversal of 33381661 is 16618333.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26522500 + 6859161 = 5150^2 + 2619^2 .

It is a cyclic number.

It is not a de Polignac number, because 33381661 - 2⁵ = 33381629 is a prime.

It is a super-2 number, since 2×33381661² = 2228670582237842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33381641) 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, 16690830 + 16690831.

It is an arithmetic number, because the mean of its divisors is an integer number (16690831).

Almost surely, 2^33381661 is an apocalyptic number.

It is an amenable number.

33381661 is a deficient number, since it is larger than the sum of its proper divisors (1).

33381661 is an equidigital number, since it uses as much as digits as its factorization.

33381661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 31.

The square root of 33381661 is about 5777.6864747059. The cubic root of 33381661 is about 321.9852525941.

Adding to 33381661 its reverse (16618333), we get a palindrome (49999994).

The spelling of 33381661 in words is "thirty-three million, three hundred eighty-one thousand, six hundred sixty-one".