81475171 has 2 divisors, whose sum is σ = 81475172. Its totient is φ = 81475170.

The previous prime is 81475157. The next prime is 81475187. The reversal of 81475171 is 17157418.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81475171 is a prime.

It is not a weakly prime, because it can be changed into another prime (81479171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40737585 + 40737586.

It is an arithmetic number, because the mean of its divisors is an integer number (40737586).

Almost surely, 2^81475171 is an apocalyptic number.

81475171 is a deficient number, since it is larger than the sum of its proper divisors (1).

81475171 is an equidigital number, since it uses as much as digits as its factorization.

81475171 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7840, while the sum is 34.

The square root of 81475171 is about 9026.3597867579. The cubic root of 81475171 is about 433.5192901427.

The spelling of 81475171 in words is "eighty-one million, four hundred seventy-five thousand, one hundred seventy-one".