21000112209 has 24 divisors (see below), whose sum is σ = 30402358272. Its totient is φ = 13968339840.

The previous prime is 21000112207. The next prime is 21000112247. The reversal of 21000112209 is 90221100012.

It is not a de Polignac number, because 21000112209 - 2¹ = 21000112207 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000112191 and 21000112200.

It is not an unprimeable number, because it can be changed into a prime (21000112207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14275344 + ... + 14276814.

It is an arithmetic number, because the mean of its divisors is an integer number (1266764928).

Almost surely, 2^21000112209 is an apocalyptic number.

It is an amenable number.

21000112209 is a deficient number, since it is larger than the sum of its proper divisors (9402246063).

21000112209 is a wasteful number, since it uses less digits than its factorization.

21000112209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3997 (or 3994 counting only the distinct ones).

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

The spelling of 21000112209 in words is "twenty-one billion, one hundred twelve thousand, two hundred nine".