100231201991 has 2 divisors, whose sum is σ = 100231201992. Its totient is φ = 100231201990.

The previous prime is 100231201937. The next prime is 100231202033. The reversal of 100231201991 is 199102132001.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 100231201991 - 2³⁴ = 83051332807 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100231201691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50115600995 + 50115600996.

It is an arithmetic number, because the mean of its divisors is an integer number (50115600996).

Almost surely, 2^100231201991 is an apocalyptic number.

100231201991 is a deficient number, since it is larger than the sum of its proper divisors (1).

100231201991 is an equidigital number, since it uses as much as digits as its factorization.

100231201991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 29.

Adding to 100231201991 its reverse (199102132001), we get a palindrome (299333333992).

The spelling of 100231201991 in words is "one hundred billion, two hundred thirty-one million, two hundred one thousand, nine hundred ninety-one".