81848131 has 2 divisors, whose sum is σ = 81848132. Its totient is φ = 81848130.

The previous prime is 81848119. The next prime is 81848141. The reversal of 81848131 is 13184818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81848131 - 2⁷ = 81848003 is a prime.

It is a super-2 number, since 2×81848131² = 13398233096386322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81848141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40924065 + 40924066.

It is an arithmetic number, because the mean of its divisors is an integer number (40924066).

Almost surely, 2^81848131 is an apocalyptic number.

81848131 is a deficient number, since it is larger than the sum of its proper divisors (1).

81848131 is an equidigital number, since it uses as much as digits as its factorization.

81848131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6144, while the sum is 34.

The square root of 81848131 is about 9046.9956891777. The cubic root of 81848131 is about 434.1797746730.

The spelling of 81848131 in words is "eighty-one million, eight hundred forty-eight thousand, one hundred thirty-one".