33221221 has 8 divisors (see below), whose sum is σ = 36297504. Its totient is φ = 30154320.

The previous prime is 33221197. The next prime is 33221249. The reversal of 33221221 is 12212233.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 33221221 - 2⁷ = 33221093 is a prime.

It is a super-4 number, since 4×33221221⁴ (a number of 31 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 33221195 and 33221204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33221261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6550 + ... + 10456.

It is an arithmetic number, because the mean of its divisors is an integer number (4537188).

Almost surely, 2^33221221 is an apocalyptic number.

It is an amenable number.

33221221 is a deficient number, since it is larger than the sum of its proper divisors (3076283).

33221221 is a wasteful number, since it uses less digits than its factorization.

33221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4691.

The product of its digits is 144, while the sum is 16.

The square root of 33221221 is about 5763.7853013449. The cubic root of 33221221 is about 321.4685787051.

Adding to 33221221 its reverse (12212233), we get a palindrome (45433454).

It can be divided in two parts, 332212 and 21, that added together give a palindrome (332233).

The spelling of 33221221 in words is "thirty-three million, two hundred twenty-one thousand, two hundred twenty-one".