813871 has 2 divisors, whose sum is σ = 813872. Its totient is φ = 813870.

The previous prime is 813863. The next prime is 813893. The reversal of 813871 is 178318.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 813871 - 2³ = 813863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (813811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406935 + 406936.

It is an arithmetic number, because the mean of its divisors is an integer number (406936).

2⁸¹³⁸⁷¹ is an apocalyptic number.

813871 is a deficient number, since it is larger than the sum of its proper divisors (1).

813871 is an equidigital number, since it uses as much as digits as its factorization.

813871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1344, while the sum is 28.

The square root of 813871 is about 902.1479922939. The cubic root of 813871 is about 93.3652342766.

The spelling of 813871 in words is "eight hundred thirteen thousand, eight hundred seventy-one".