21340033 has 16 divisors (see below), whose sum is σ = 25401600. Its totient is φ = 17671680.

The previous prime is 21340019. The next prime is 21340051. The reversal of 21340033 is 33004312.

It is not a de Polignac number, because 21340033 - 2¹⁷ = 21208961 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21339989 and 21340016.

It is not an unprimeable number, because it can be changed into a prime (21340003) 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, 10353 + ... + 12241.

It is an arithmetic number, because the mean of its divisors is an integer number (1587600).

Almost surely, 2^21340033 is an apocalyptic number.

It is an amenable number.

21340033 is a deficient number, since it is larger than the sum of its proper divisors (4061567).

21340033 is a wasteful number, since it uses less digits than its factorization.

21340033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1992.

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 21340033 is about 4619.5273567758. The cubic root of 21340033 is about 277.3735397604.

Adding to 21340033 its reverse (33004312), we get a palindrome (54344345).

The spelling of 21340033 in words is "twenty-one million, three hundred forty thousand, thirty-three".