20211522109 has 2 divisors, whose sum is σ = 20211522110. Its totient is φ = 20211522108.

The previous prime is 20211522083. The next prime is 20211522161. The reversal of 20211522109 is 90122511202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19531460025 + 680062084 = 139755^2 + 26078^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211522109 - 2²⁷ = 20077304381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20215522109) 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, 10105761054 + 10105761055.

It is an arithmetic number, because the mean of its divisors is an integer number (10105761055).

Almost surely, 2^20211522109 is an apocalyptic number.

It is an amenable number.

20211522109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211522109 is an equidigital number, since it uses as much as digits as its factorization.

20211522109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 25.

The spelling of 20211522109 in words is "twenty billion, two hundred eleven million, five hundred twenty-two thousand, one hundred nine".