71813 has 4 divisors (see below), whose sum is σ = 82080. Its totient is φ = 61548.

The previous prime is 71809. The next prime is 71821. The reversal of 71813 is 31817.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71813 - 2² = 71809 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 (71843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5123 + ... + 5136.

It is an arithmetic number, because the mean of its divisors is an integer number (20520).

2⁷¹⁸¹³ is an apocalyptic number.

It is an amenable number.

71813 is a deficient number, since it is larger than the sum of its proper divisors (10267).

71813 is a wasteful number, since it uses less digits than its factorization.

71813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10266.

The product of its digits is 168, while the sum is 20.

The square root of 71813 is about 267.9794768261. The cubic root of 71813 is about 41.5656289690.

The spelling of 71813 in words is "seventy-one thousand, eight hundred thirteen".