20120110009991 has 2 divisors, whose sum is σ = 20120110009992. Its totient is φ = 20120110009990.

The previous prime is 20120110009969. The next prime is 20120110010029. The reversal of 20120110009991 is 19990001102102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20120110009991 - 2⁶ = 20120110009927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20110110009991) 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, 10060055004995 + 10060055004996.

It is an arithmetic number, because the mean of its divisors is an integer number (10060055004996).

Almost surely, 2^{20120110009991} is an apocalyptic number.

20120110009991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20120110009991 is an equidigital number, since it uses as much as digits as its factorization.

20120110009991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 35.

The spelling of 20120110009991 in words is "twenty trillion, one hundred twenty billion, one hundred ten million, nine thousand, nine hundred ninety-one".