871666571 has 2 divisors, whose sum is σ = 871666572. Its totient is φ = 871666570.

The previous prime is 871666513. The next prime is 871666573. The reversal of 871666571 is 175666178.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 871666571 - 2¹⁰ = 871665547 is a prime.

It is a super-2 number, since 2×871666571² = 1519605221997796082, which contains 22 as substring.

Together with 871666573, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (871666573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435833285 + 435833286.

It is an arithmetic number, because the mean of its divisors is an integer number (435833286).

Almost surely, 2^871666571 is an apocalyptic number.

871666571 is a deficient number, since it is larger than the sum of its proper divisors (1).

871666571 is an equidigital number, since it uses as much as digits as its factorization.

871666571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 423360, while the sum is 47.

The square root of 871666571 is about 29523.9999153231. Note that the first 4 decimals coincide. The cubic root of 871666571 is about 955.2494513882.

The spelling of 871666571 in words is "eight hundred seventy-one million, six hundred sixty-six thousand, five hundred seventy-one".