871643 has 2 divisors, whose sum is σ = 871644. Its totient is φ = 871642.

The previous prime is 871639. The next prime is 871649. The reversal of 871643 is 346178.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 871643 - 2² = 871639 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (871649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435821 + 435822.

It is an arithmetic number, because the mean of its divisors is an integer number (435822).

2⁸⁷¹⁶⁴³ is an apocalyptic number.

871643 is a deficient number, since it is larger than the sum of its proper divisors (1).

871643 is an equidigital number, since it uses as much as digits as its factorization.

871643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4032, while the sum is 29.

The square root of 871643 is about 933.6182303276. The cubic root of 871643 is about 95.5240840914.

The spelling of 871643 in words is "eight hundred seventy-one thousand, six hundred forty-three".