51824 has 20 divisors (see below), whose sum is σ = 104160. Its totient is φ = 24960.

The previous prime is 51817. The next prime is 51827. The reversal of 51824 is 42815.

It is an Ulam number.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 51796 and 51805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51827) by changing a digit.

51824 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 617 + ... + 695.

It is an arithmetic number, because the mean of its divisors is an integer number (5208).

2⁵¹⁸²⁴ is an apocalyptic number.

It is an amenable number.

51824 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52080).

51824 is a wasteful number, since it uses less digits than its factorization.

51824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 122 counting only the distinct ones).

The product of its digits is 320, while the sum is 20.

The square root of 51824 is about 227.6488524021. The cubic root of 51824 is about 37.2829535872.

Subtracting from 51824 its reverse (42815), we obtain a palindrome (9009).

It can be divided in two parts, 51 and 824, that multiplied together give a palindrome (42024).

The spelling of 51824 in words is "fifty-one thousand, eight hundred twenty-four".