33855221 has 4 divisors (see below), whose sum is σ = 33882432. Its totient is φ = 33828012.

The previous prime is 33855187. The next prime is 33855223. The reversal of 33855221 is 12255833.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12255833 = 349 ⋅35117.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33855221 is a prime.

It is a super-2 number, since 2×33855221² = 2292351977917682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33855223) 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, 11645 + ... + 14258.

It is an arithmetic number, because the mean of its divisors is an integer number (8470608).

Almost surely, 2^33855221 is an apocalyptic number.

It is an amenable number.

33855221 is a deficient number, since it is larger than the sum of its proper divisors (27211).

33855221 is a wasteful number, since it uses less digits than its factorization.

33855221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27210.

The product of its digits is 7200, while the sum is 29.

The square root of 33855221 is about 5818.5239537188. The cubic root of 33855221 is about 323.5006947598.

The spelling of 33855221 in words is "thirty-three million, eight hundred fifty-five thousand, two hundred twenty-one".