81190637399231 has 2 divisors, whose sum is σ = 81190637399232. Its totient is φ = 81190637399230.

The previous prime is 81190637399171. The next prime is 81190637399233. The reversal of 81190637399231 is 13299373609118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81190637399231 - 2¹⁸ = 81190637137087 is a prime.

It is a super-2 number, since 2×81190637399231² (a number of 29 digits) contains 22 as substring.

Together with 81190637399233, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81190637399233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40595318699615 + 40595318699616.

It is an arithmetic number, because the mean of its divisors is an integer number (40595318699616).

Almost surely, 2^{81190637399231} is an apocalyptic number.

81190637399231 is a deficient number, since it is larger than the sum of its proper divisors (1).

81190637399231 is an equidigital number, since it uses as much as digits as its factorization.

81190637399231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13226976, while the sum is 62.

The spelling of 81190637399231 in words is "eighty-one trillion, one hundred ninety billion, six hundred thirty-seven million, three hundred ninety-nine thousand, two hundred thirty-one".