54821 has 4 divisors (see below), whose sum is σ = 59052. Its totient is φ = 50592.

The previous prime is 54799. The next prime is 54829. The reversal of 54821 is 12845.

54821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 28900 + 25921 = 170^2 + 161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-54821 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 54793 and 54802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2096 + ... + 2121.

It is an arithmetic number, because the mean of its divisors is an integer number (14763).

2⁵⁴⁸²¹ is an apocalyptic number.

It is an amenable number.

54821 is a deficient number, since it is larger than the sum of its proper divisors (4231).

54821 is a wasteful number, since it uses less digits than its factorization.

54821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4230.

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

The square root of 54821 is about 234.1388476951. The cubic root of 54821 is about 37.9882234976.

The spelling of 54821 in words is "fifty-four thousand, eight hundred twenty-one".