101011231991 has 2 divisors, whose sum is σ = 101011231992. Its totient is φ = 101011231990.

The previous prime is 101011231949. The next prime is 101011232099. The reversal of 101011231991 is 199132110101.

It is a weak prime.

It is an emirp because it is prime and its reverse (199132110101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101011231991 - 2⁶ = 101011231927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101011231921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50505615995 + 50505615996.

It is an arithmetic number, because the mean of its divisors is an integer number (50505615996).

Almost surely, 2^101011231991 is an apocalyptic number.

101011231991 is a deficient number, since it is larger than the sum of its proper divisors (1).

101011231991 is an equidigital number, since it uses as much as digits as its factorization.

101011231991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 29.

The spelling of 101011231991 in words is "one hundred one billion, eleven million, two hundred thirty-one thousand, nine hundred ninety-one".