21042033 has 12 divisors (see below), whose sum is σ = 29331120. Its totient is φ = 13417096.

The previous prime is 21042017. The next prime is 21042053. The reversal of 21042033 is 33024012.

It is not a de Polignac number, because 21042033 - 2⁴ = 21042017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21042013) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5043 + ... + 8216.

It is an arithmetic number, because the mean of its divisors is an integer number (2444260).

Almost surely, 2^21042033 is an apocalyptic number.

21042033 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21042033 is a deficient number, since it is larger than the sum of its proper divisors (8289087).

21042033 is a wasteful number, since it uses less digits than its factorization.

21042033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13308 (or 13285 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21042033 is about 4587.1595786500. The cubic root of 21042033 is about 276.0763677564.

Adding to 21042033 its reverse (33024012), we get a palindrome (54066045).

The spelling of 21042033 in words is "twenty-one million, forty-two thousand, thirty-three".