20211211109 has 2 divisors, whose sum is σ = 20211211110. Its totient is φ = 20211211108.

The previous prime is 20211211091. The next prime is 20211211117. The reversal of 20211211109 is 90111211202.

Together with previous prime (20211211091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10936558084 + 9274653025 = 104578^2 + 96305^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211211109 - 2²⁴ = 20194433893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20211211169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105605554 + 10105605555.

It is an arithmetic number, because the mean of its divisors is an integer number (10105605555).

Almost surely, 2^20211211109 is an apocalyptic number.

It is an amenable number.

20211211109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211211109 is an equidigital number, since it uses as much as digits as its factorization.

20211211109 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 20.

The spelling of 20211211109 in words is "twenty billion, two hundred eleven million, two hundred eleven thousand, one hundred nine".