81190637399171 has 2 divisors, whose sum is σ = 81190637399172. Its totient is φ = 81190637399170.

The previous prime is 81190637399107. The next prime is 81190637399231. The reversal of 81190637399171 is 17199373609118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81190637399171 - 2⁶ = 81190637399107 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81190637399098 and 81190637399107.

It is not a weakly prime, because it can be changed into another prime (81190637399101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40595318699585 + 40595318699586.

It is an arithmetic number, because the mean of its divisors is an integer number (40595318699586).

Almost surely, 2^{81190637399171} is an apocalyptic number.

81190637399171 is a deficient number, since it is larger than the sum of its proper divisors (1).

81190637399171 is an equidigital number, since it uses as much as digits as its factorization.

81190637399171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15431472, while the sum is 65.

The spelling of 81190637399171 in words is "eighty-one trillion, one hundred ninety billion, six hundred thirty-seven million, three hundred ninety-nine thousand, one hundred seventy-one".