51428 has 24 divisors (see below), whose sum is σ = 103488.
Its totient is φ = 22176.
The previous prime is 51427. The next prime is 51431. The reversal of 51428 is 82415.
It can be divided in two parts, 5 and 1428, that multiplied together give a triangular number (7140 = T119).
It is a Smith number, since the sum of its digits (20) coincides with the sum of the digits of its prime factors.
It is an Ulam number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 51428.
It is not an unprimeable number, because it can be changed into a prime (51421) 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 7 ways as a sum of consecutive naturals, for example, 1175 + ... + 1217.
It is an arithmetic number, because the mean of its divisors is an integer number (4312).
251428 is an apocalyptic number.
It is an amenable number.
51428 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 (51744).
51428 is a wasteful number, since it uses less digits than its factorization.
51428 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 83 (or 81 counting only the distinct ones).
The product of its digits is 320, while the sum is 20.
The square root of 51428 is about 226.7774239205.
Note that the first 3 decimals coincide.
The cubic root of 51428 is about 37.1877479210.
The spelling of 51428 in words is "fifty-one thousand, four hundred twenty-eight".