243871 has 2 divisors, whose sum is σ = 243872. Its totient is φ = 243870.

The previous prime is 243863. The next prime is 243889. The reversal of 243871 is 178342.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 243871 - 2³ = 243863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121935 + 121936.

It is an arithmetic number, because the mean of its divisors is an integer number (121936).

2²⁴³⁸⁷¹ is an apocalyptic number.

243871 is a deficient number, since it is larger than the sum of its proper divisors (1).

243871 is an equidigital number, since it uses as much as digits as its factorization.

243871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1344, while the sum is 25.

The square root of 243871 is about 493.8329677128. The cubic root of 243871 is about 62.4769835249.

The spelling of 243871 in words is "two hundred forty-three thousand, eight hundred seventy-one".