71731 has 4 divisors (see below), whose sum is σ = 78264. Its totient is φ = 65200.

The previous prime is 71719. The next prime is 71741. The reversal of 71731 is 13717.

It is a happy number.

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 71731 - 2⁵ = 71699 is a prime.

It is a super-2 number, since 2×71731² = 10290672722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71699 and 71708.

It is not an unprimeable number, because it can be changed into a prime (71711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3250 + ... + 3271.

It is an arithmetic number, because the mean of its divisors is an integer number (19566).

2⁷¹⁷³¹ is an apocalyptic number.

71731 is a deficient number, since it is larger than the sum of its proper divisors (6533).

71731 is a wasteful number, since it uses less digits than its factorization.

71731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6532.

The product of its digits is 147, while the sum is 19.

The square root of 71731 is about 267.8264363352. The cubic root of 71731 is about 41.5498023095.

The spelling of 71731 in words is "seventy-one thousand, seven hundred thirty-one".