51810 has 32 divisors (see below), whose sum is σ = 136512. Its totient is φ = 12480.

The previous prime is 51803. The next prime is 51817. The reversal of 51810 is 1815.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51803) and next prime (51817).

It is a super-2 number, since 2×51810² = 5368552200, which contains 22 as substring.

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

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 51810.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 51810.

It is not an unprimeable number, because it can be changed into a prime (51817) 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 15 ways as a sum of consecutive naturals, for example, 252 + ... + 408.

It is an arithmetic number, because the mean of its divisors is an integer number (4266).

2⁵¹⁸¹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51810, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68256).

51810 is an abundant number, since it is smaller than the sum of its proper divisors (84702).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51810 is a wasteful number, since it uses less digits than its factorization.

51810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 51810 is about 227.6181012134. The cubic root of 51810 is about 37.2795960157.

It can be divided in two parts, 518 and 10, that added together give a triangular number (528 = T₃₂).

The spelling of 51810 in words is "fifty-one thousand, eight hundred ten".