33856221 has 16 divisors (see below), whose sum is σ = 52985984. Its totient is φ = 18823104.

The previous prime is 33856219. The next prime is 33856237. The reversal of 33856221 is 12265833.

It is not a de Polignac number, because 33856221 - 2¹ = 33856219 is a prime.

It is a super-2 number, since 2×33856221² = 2292487400801682, 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 (33856211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21010 + ... + 22563.

It is an arithmetic number, because the mean of its divisors is an integer number (3311624).

Almost surely, 2^33856221 is an apocalyptic number.

It is an amenable number.

33856221 is a deficient number, since it is larger than the sum of its proper divisors (19129763).

33856221 is a wasteful number, since it uses less digits than its factorization.

33856221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43620.

The product of its digits is 8640, while the sum is 30.

The square root of 33856221 is about 5818.6098855311. The cubic root of 33856221 is about 323.5038798669.

The spelling of 33856221 in words is "thirty-three million, eight hundred fifty-six thousand, two hundred twenty-one".