20291911109 has 2 divisors, whose sum is σ = 20291911110. Its totient is φ = 20291911108.

The previous prime is 20291911049. The next prime is 20291911121. The reversal of 20291911109 is 90111919202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19196102500 + 1095808609 = 138550^2 + 33103^2 .

It is a cyclic number.

It is not a de Polignac number, because 20291911109 - 2⁸ = 20291910853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20291911139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10145955554 + 10145955555.

It is an arithmetic number, because the mean of its divisors is an integer number (10145955555).

Almost surely, 2^20291911109 is an apocalyptic number.

It is an amenable number.

20291911109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20291911109 is an equidigital number, since it uses as much as digits as its factorization.

20291911109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 35.

The spelling of 20291911109 in words is "twenty billion, two hundred ninety-one million, nine hundred eleven thousand, one hundred nine".