33320021 has 4 divisors (see below), whose sum is σ = 38080032. Its totient is φ = 28560012.

The previous prime is 33320011. The next prime is 33320033. The reversal of 33320021 is 12002333.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33320021 is a prime.

It is a super-2 number, since 2×33320021² = 2220447598880882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 33319978 and 33320005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33320011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2379995 + ... + 2380008.

It is an arithmetic number, because the mean of its divisors is an integer number (9520008).

Almost surely, 2^33320021 is an apocalyptic number.

It is an amenable number.

33320021 is a deficient number, since it is larger than the sum of its proper divisors (4760011).

33320021 is an equidigital number, since it uses as much as digits as its factorization.

33320021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4760010.

The product of its (nonzero) digits is 108, while the sum is 14.

The square root of 33320021 is about 5772.3496948816. The cubic root of 33320021 is about 321.7869461088.

Adding to 33320021 its reverse (12002333), we get a palindrome (45322354).

The spelling of 33320021 in words is "thirty-three million, three hundred twenty thousand, twenty-one".