33121331 has 2 divisors, whose sum is σ = 33121332. Its totient is φ = 33121330.

The previous prime is 33121307. The next prime is 33121339. The reversal of 33121331 is 13312133.

It is a strong prime.

It is an emirp because it is prime and its reverse (13312133) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33121331 is a prime.

It is a super-2 number, since 2×33121331² = 2194045134423122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (33121339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16560665 + 16560666.

It is an arithmetic number, because the mean of its divisors is an integer number (16560666).

Almost surely, 2^33121331 is an apocalyptic number.

33121331 is a deficient number, since it is larger than the sum of its proper divisors (1).

33121331 is an equidigital number, since it uses as much as digits as its factorization.

33121331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162, while the sum is 17.

The square root of 33121331 is about 5755.1134654323. The cubic root of 33121331 is about 321.1460565977.

Adding to 33121331 its reverse (13312133), we get a palindrome (46433464).

The spelling of 33121331 in words is "thirty-three million, one hundred twenty-one thousand, three hundred thirty-one".