63871 has 4 divisors (see below), whose sum is σ = 66672. Its totient is φ = 61072.

The previous prime is 63863. The next prime is 63901. The reversal of 63871 is 17836.

63871 = T₂₈ + T₂₉ + ... + T₇₃.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 63871 - 2³ = 63863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1366 + ... + 1411.

It is an arithmetic number, because the mean of its divisors is an integer number (16668).

2⁶³⁸⁷¹ is an apocalyptic number.

63871 is a deficient number, since it is larger than the sum of its proper divisors (2801).

63871 is a wasteful number, since it uses less digits than its factorization.

63871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2800.

The product of its digits is 1008, while the sum is 25.

The square root of 63871 is about 252.7271255722. The cubic root of 63871 is about 39.9731069231.

The spelling of 63871 in words is "sixty-three thousand, eight hundred seventy-one".