33813021 has 16 divisors (see below), whose sum is σ = 49446720. Its totient is φ = 20382720.

The previous prime is 33813019. The next prime is 33813037. The reversal of 33813021 is 12031833.

It is a happy number.

It is not a de Polignac number, because 33813021 - 2¹ = 33813019 is a prime.

It is a super-2 number, since 2×33813021² = 2286640778292882, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33813061) 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, 3715 + ... + 9023.

It is an arithmetic number, because the mean of its divisors is an integer number (3090420).

Almost surely, 2^33813021 is an apocalyptic number.

It is an amenable number.

33813021 is a deficient number, since it is larger than the sum of its proper divisors (15633699).

33813021 is a wasteful number, since it uses less digits than its factorization.

33813021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5516.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 33813021 is about 5814.8964737130. The cubic root of 33813021 is about 323.3662260322.

Adding to 33813021 its reverse (12031833), we get a palindrome (45844854).

The spelling of 33813021 in words is "thirty-three million, eight hundred thirteen thousand, twenty-one".