51709 has 8 divisors (see below), whose sum is σ = 60480. Its totient is φ = 43296.

The previous prime is 51691. The next prime is 51713. The reversal of 51709 is 90715.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51709 - 2⁷ = 51581 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 537 + ... + 625.

It is an arithmetic number, because the mean of its divisors is an integer number (7560).

2⁵¹⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

51709 is a deficient number, since it is larger than the sum of its proper divisors (8771).

51709 is an equidigital number, since it uses as much as digits as its factorization.

51709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179.

The product of its (nonzero) digits is 315, while the sum is 22.

The square root of 51709 is about 227.3961301342. The cubic root of 51709 is about 37.2553555953.

The spelling of 51709 in words is "fifty-one thousand, seven hundred nine".