33218161 has 2 divisors, whose sum is σ = 33218162. Its totient is φ = 33218160.

The previous prime is 33218149. The next prime is 33218183. The reversal of 33218161 is 16181233.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31640625 + 1577536 = 5625^2 + 1256^2 .

It is a cyclic number.

It is not a de Polignac number, because 33218161 - 2¹⁵ = 33185393 is a prime.

It is a super-2 number, since 2×33218161² = 2206892440443842, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (33218191) 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, 16609080 + 16609081.

It is an arithmetic number, because the mean of its divisors is an integer number (16609081).

Almost surely, 2^33218161 is an apocalyptic number.

It is an amenable number.

33218161 is a deficient number, since it is larger than the sum of its proper divisors (1).

33218161 is an equidigital number, since it uses as much as digits as its factorization.

33218161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 25.

The square root of 33218161 is about 5763.5198446783. The cubic root of 33218161 is about 321.4587082666.

Adding to 33218161 its reverse (16181233), we get a palindrome (49399394).

The spelling of 33218161 in words is "thirty-three million, two hundred eighteen thousand, one hundred sixty-one".