20110110009991 has 2 divisors, whose sum is σ = 20110110009992. Its totient is φ = 20110110009990.

The previous prime is 20110110009923. The next prime is 20110110010093. The reversal of 20110110009991 is 19990001101102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20110110009991 - 2²⁹ = 20109573139079 is a prime.

It is a super-2 number, since 2×20110110009991² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20110110009391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055055004995 + 10055055004996.

It is an arithmetic number, because the mean of its divisors is an integer number (10055055004996).

Almost surely, 2^{20110110009991} is an apocalyptic number.

20110110009991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20110110009991 is an equidigital number, since it uses as much as digits as its factorization.

20110110009991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1458, while the sum is 34.

The spelling of 20110110009991 in words is "twenty trillion, one hundred ten billion, one hundred ten million, nine thousand, nine hundred ninety-one".