21033110209 has 16 divisors (see below), whose sum is σ = 22582540800. Its totient is φ = 19519593984.

The previous prime is 21033110191. The next prime is 21033110251. The reversal of 21033110209 is 90201133012.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033110209 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21033110209.

It is not an unprimeable number, because it can be changed into a prime (21033110279) 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, 536332 + ... + 574210.

It is an arithmetic number, because the mean of its divisors is an integer number (1411408800).

Almost surely, 2^21033110209 is an apocalyptic number.

It is an amenable number.

21033110209 is a deficient number, since it is larger than the sum of its proper divisors (1549430591).

21033110209 is a wasteful number, since it uses less digits than its factorization.

21033110209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38352.

The product of its (nonzero) digits is 324, while the sum is 22.

The spelling of 21033110209 in words is "twenty-one billion, thirty-three million, one hundred ten thousand, two hundred nine".