20201211021191 has 2 divisors, whose sum is σ = 20201211021192. Its totient is φ = 20201211021190.

The previous prime is 20201211021161. The next prime is 20201211021263. The reversal of 20201211021191 is 19112011210202.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20201211021191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20201211021161) 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, 10100605510595 + 10100605510596.

It is an arithmetic number, because the mean of its divisors is an integer number (10100605510596).

Almost surely, 2^{20201211021191} is an apocalyptic number.

20201211021191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20201211021191 is an equidigital number, since it uses as much as digits as its factorization.

20201211021191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 23.

Adding to 20201211021191 its reverse (19112011210202), we get a palindrome (39313222231393).

The spelling of 20201211021191 in words is "twenty trillion, two hundred one billion, two hundred eleven million, twenty-one thousand, one hundred ninety-one".