33000021 has 16 divisors (see below), whose sum is σ = 49022400. Its totient is φ = 21939984.

The previous prime is 33000007. The next prime is 33000029. The reversal of 33000021 is 12000033.

It is a happy number.

It is not a de Polignac number, because 33000021 - 2¹¹ = 32997973 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 32999967 and 33000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33000029) 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, 9855 + ... + 12771.

It is an arithmetic number, because the mean of its divisors is an integer number (3063900).

Almost surely, 2^33000021 is an apocalyptic number.

It is an amenable number.

33000021 is a deficient number, since it is larger than the sum of its proper divisors (16022379).

33000021 is a wasteful number, since it uses less digits than its factorization.

33000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3345 (or 3339 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 9.

The square root of 33000021 is about 5744.5644743531. The cubic root of 33000021 is about 320.7535010382.

Adding to 33000021 its reverse (12000033), we get a palindrome (45000054).

The spelling of 33000021 in words is "thirty-three million, twenty-one", and thus it is an aban number and an uban number.