20012089991 has 2 divisors, whose sum is σ = 20012089992. Its totient is φ = 20012089990.

The previous prime is 20012089919. The next prime is 20012089997. The reversal of 20012089991 is 19998021002.

Together with previous prime (20012089919) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20012089991 - 2¹⁴ = 20012073607 is a prime.

It is a super-3 number, since 3×20012089991³ (a number of 32 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20012089997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006044995 + 10006044996.

It is an arithmetic number, because the mean of its divisors is an integer number (10006044996).

Almost surely, 2^20012089991 is an apocalyptic number.

20012089991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012089991 is an equidigital number, since it uses as much as digits as its factorization.

20012089991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 41.

The spelling of 20012089991 in words is "twenty billion, twelve million, eighty-nine thousand, nine hundred ninety-one".