33220391 has 2 divisors, whose sum is σ = 33220392. Its totient is φ = 33220390.

The previous prime is 33220387. The next prime is 33220393. The reversal of 33220391 is 19302233.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 33220391 - 2² = 33220387 is a prime.

It is a super-2 number, since 2×33220391² = 2207188756385762, which contains 22 as substring.

Together with 33220393, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33220393) 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, 16610195 + 16610196.

It is an arithmetic number, because the mean of its divisors is an integer number (16610196).

Almost surely, 2^33220391 is an apocalyptic number.

33220391 is a deficient number, since it is larger than the sum of its proper divisors (1).

33220391 is an equidigital number, since it uses as much as digits as its factorization.

33220391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 23.

The square root of 33220391 is about 5763.7132996012. The cubic root of 33220391 is about 321.4659014892.

The spelling of 33220391 in words is "thirty-three million, two hundred twenty thousand, three hundred ninety-one".