20012230991 has 2 divisors, whose sum is σ = 20012230992. Its totient is φ = 20012230990.

The previous prime is 20012230961. The next prime is 20012230993. The reversal of 20012230991 is 19903221002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20012230991 is a prime.

Together with 20012230993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20012230993) 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, 10006115495 + 10006115496.

It is an arithmetic number, because the mean of its divisors is an integer number (10006115496).

Almost surely, 2^20012230991 is an apocalyptic number.

20012230991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012230991 is an equidigital number, since it uses as much as digits as its factorization.

20012230991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

Adding to 20012230991 its reverse (19903221002), we get a palindrome (39915451993).

The spelling of 20012230991 in words is "twenty billion, twelve million, two hundred thirty thousand, nine hundred ninety-one".