20001211209 has 24 divisors (see below), whose sum is σ = 33037971200. Its totient is φ = 11422306368.

The previous prime is 20001211199. The next prime is 20001211211. The reversal of 20001211209 is 90211210002.

It is not a de Polignac number, because 20001211209 - 2⁴ = 20001211193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20001211191 and 20001211200.

It is not an unprimeable number, because it can be changed into a prime (20001211409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8592 + ... + 200190.

Almost surely, 2^20001211209 is an apocalyptic number.

It is an amenable number.

20001211209 is a deficient number, since it is larger than the sum of its proper divisors (13036759991).

20001211209 is a wasteful number, since it uses less digits than its factorization.

20001211209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193269 (or 193266 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The spelling of 20001211209 in words is "twenty billion, one million, two hundred eleven thousand, two hundred nine".