20011210091 has 2 divisors, whose sum is σ = 20011210092. Its totient is φ = 20011210090.

The previous prime is 20011210081. The next prime is 20011210123. The reversal of 20011210091 is 19001211002.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011210091 is a prime.

It is a super-2 number, since 2×20011210091² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20011210061) 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, 10005605045 + 10005605046.

It is an arithmetic number, because the mean of its divisors is an integer number (10005605046).

Almost surely, 2^20011210091 is an apocalyptic number.

20011210091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011210091 is an equidigital number, since it uses as much as digits as its factorization.

20011210091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 17.

Adding to 20011210091 its reverse (19001211002), we get a palindrome (39012421093).

The spelling of 20011210091 in words is "twenty billion, eleven million, two hundred ten thousand, ninety-one".