21221020200209 has 16 divisors (see below), whose sum is σ = 23341548902400. Its totient is φ = 19203286226256.

The previous prime is 21221020200173. The next prime is 21221020200223. The reversal of 21221020200209 is 90200202012212.

It is a cyclic number.

It is not a de Polignac number, because 21221020200209 - 2¹² = 21221020196113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221020209209) 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, 33455399 + ... + 34083804.

It is an arithmetic number, because the mean of its divisors is an integer number (1458846806400).

Almost surely, 2^{21221020200209} is an apocalyptic number.

It is an amenable number.

21221020200209 is a deficient number, since it is larger than the sum of its proper divisors (2120528702191).

21221020200209 is a wasteful number, since it uses less digits than its factorization.

21221020200209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67539964.

The product of its (nonzero) digits is 576, while the sum is 23.

The spelling of 21221020200209 in words is "twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred thousand, two hundred nine".