21321110203109 has 2 divisors, whose sum is σ = 21321110203110. Its totient is φ = 21321110203108.

The previous prime is 21321110203103. The next prime is 21321110203147. The reversal of 21321110203109 is 90130201112312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19056979084900 + 2264131118209 = 4365430^2 + 1504703^2 .

It is a cyclic number.

It is not a de Polignac number, because 21321110203109 - 2¹² = 21321110199013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21321110203103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660555101554 + 10660555101555.

It is an arithmetic number, because the mean of its divisors is an integer number (10660555101555).

Almost surely, 2^{21321110203109} is an apocalyptic number.

It is an amenable number.

21321110203109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21321110203109 is an equidigital number, since it uses as much as digits as its factorization.

21321110203109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 26.

The spelling of 21321110203109 in words is "twenty-one trillion, three hundred twenty-one billion, one hundred ten million, two hundred three thousand, one hundred nine".