20543312191 has 2 divisors, whose sum is σ = 20543312192. Its totient is φ = 20543312190.

The previous prime is 20543312177. The next prime is 20543312197. The reversal of 20543312191 is 19121334502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20543312191 - 2²⁷ = 20409094463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20543312197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10271656095 + 10271656096.

It is an arithmetic number, because the mean of its divisors is an integer number (10271656096).

Almost surely, 2^20543312191 is an apocalyptic number.

20543312191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20543312191 is an equidigital number, since it uses as much as digits as its factorization.

20543312191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 31.

Adding to 20543312191 its reverse (19121334502), we get a palindrome (39664646693).

The spelling of 20543312191 in words is "twenty billion, five hundred forty-three million, three hundred twelve thousand, one hundred ninety-one".