21032112209 has 2 divisors, whose sum is σ = 21032112210. Its totient is φ = 21032112208.

The previous prime is 21032112133. The next prime is 21032112217. The reversal of 21032112209 is 90221123012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20837788609 + 194323600 = 144353^2 + 13940^2 .

It is a cyclic number.

It is not a de Polignac number, because 21032112209 - 2²⁴ = 21015334993 is a prime.

It is not a weakly prime, because it can be changed into another prime (21032112259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516056104 + 10516056105.

It is an arithmetic number, because the mean of its divisors is an integer number (10516056105).

Almost surely, 2^21032112209 is an apocalyptic number.

It is an amenable number.

21032112209 is a deficient number, since it is larger than the sum of its proper divisors (1).

21032112209 is an equidigital number, since it uses as much as digits as its factorization.

21032112209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

The spelling of 21032112209 in words is "twenty-one billion, thirty-two million, one hundred twelve thousand, two hundred nine".