21000220101109 has 2 divisors, whose sum is σ = 21000220101110. Its totient is φ = 21000220101108.

The previous prime is 21000220101101. The next prime is 21000220101167. The reversal of 21000220101109 is 90110102200012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20518209268209 + 482010832900 = 4529703^2 + 694270^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000220101109 - 2³ = 21000220101101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000220101101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500110050554 + 10500110050555.

It is an arithmetic number, because the mean of its divisors is an integer number (10500110050555).

Almost surely, 2^{21000220101109} is an apocalyptic number.

It is an amenable number.

21000220101109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000220101109 is an equidigital number, since it uses as much as digits as its factorization.

21000220101109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21000220101109 in words is "twenty-one trillion, two hundred twenty million, one hundred one thousand, one hundred nine".