21212020102209 has 16 divisors (see below), whose sum is σ = 28368411952320. Its totient is φ = 14098516689600.

The previous prime is 21212020102181. The next prime is 21212020102219. The reversal of 21212020102209 is 90220102021212.

It is not a de Polignac number, because 21212020102209 - 2⁵ = 21212020102177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21212020102219) 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, 740742 + ... + 6555359.

It is an arithmetic number, because the mean of its divisors is an integer number (1773025747020).

Almost surely, 2^{21212020102209} is an apocalyptic number.

It is an amenable number.

21212020102209 is a deficient number, since it is larger than the sum of its proper divisors (7156391850111).

21212020102209 is a wasteful number, since it uses less digits than its factorization.

21212020102209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7299040.

The product of its (nonzero) digits is 576, while the sum is 24.

The spelling of 21212020102209 in words is "twenty-one trillion, two hundred twelve billion, twenty million, one hundred two thousand, two hundred nine".