51315 has 16 divisors (see below), whose sum is σ = 89856. Its totient is φ = 24800.

The previous prime is 51307. The next prime is 51329.

51315 is nontrivially palindromic in base 10.

51315 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51315 - 2³ = 51307 is a prime.

It is a Smith number, since the sum of its digits (15) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nude number because it is divisible by every one of its digits.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 51294 and 51303.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10 + ... + 320.

It is an arithmetic number, because the mean of its divisors is an integer number (5616).

2⁵¹³¹⁵ is an apocalyptic number.

51315 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51315 is a deficient number, since it is larger than the sum of its proper divisors (38541).

51315 is a wasteful number, since it uses less digits than its factorization.

51315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330.

The product of its digits is 75, while the sum is 15.

The square root of 51315 is about 226.5281439468. The cubic root of 51315 is about 37.1604910633.

It can be divided in two parts, 513 and 15, that added together give a triangular number (528 = T₃₂).

The spelling of 51315 in words is "fifty-one thousand, three hundred fifteen".