51444 has 18 divisors (see below), whose sum is σ = 130130. Its totient is φ = 17136.

The previous prime is 51439. The next prime is 51449. The reversal of 51444 is 44415.

51444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51439) and next prime (51449).

It can be written as a sum of positive squares in only one way, i.e., 32400 + 19044 = 180^2 + 138^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51449) by changing a digit.

51444 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 679 + ... + 750.

2⁵¹⁴⁴⁴ is an apocalyptic number.

It is an amenable number.

51444 is an abundant number, since it is smaller than the sum of its proper divisors (78686).

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

51444 is a wasteful number, since it uses less digits than its factorization.

51444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1439 (or 1434 counting only the distinct ones).

The product of its digits is 320, while the sum is 18.

The square root of 51444 is about 226.8126980572. The cubic root of 51444 is about 37.1916040712.

Adding to 51444 its reverse (44415), we get a palindrome (95859).

The spelling of 51444 in words is "fifty-one thousand, four hundred forty-four".