71851 has 4 divisors (see below), whose sum is σ = 77392. Its totient is φ = 66312.

The previous prime is 71849. The next prime is 71861. The reversal of 71851 is 15817.

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 71851 - 2¹ = 71849 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (71821) 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, 2751 + ... + 2776.

It is an arithmetic number, because the mean of its divisors is an integer number (19348).

2⁷¹⁸⁵¹ is an apocalyptic number.

71851 is a deficient number, since it is larger than the sum of its proper divisors (5541).

71851 is a wasteful number, since it uses less digits than its factorization.

71851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5540.

The product of its digits is 280, while the sum is 22.

The square root of 71851 is about 268.0503684012. The cubic root of 71851 is about 41.5729591896.

The spelling of 71851 in words is "seventy-one thousand, eight hundred fifty-one".