543721 has 4 divisors (see below), whose sum is σ = 562500. Its totient is φ = 524944.

The previous prime is 543713. The next prime is 543769. The reversal of 543721 is 127345.

543721 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, and also an emirpimes, since its reverse is a distinct semiprime: 127345 = 5 ⋅25469.

It can be written as a sum of positive squares in 2 ways, for example, as 318096 + 225625 = 564^2 + 475^2 .

It is a cyclic number.

It is not a de Polignac number, because 543721 - 2³ = 543713 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 543692 and 543701.

It is not an unprimeable number, because it can be changed into a prime (543791) 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, 9346 + ... + 9403.

It is an arithmetic number, because the mean of its divisors is an integer number (140625).

2⁵⁴³⁷²¹ is an apocalyptic number.

It is an amenable number.

543721 is a deficient number, since it is larger than the sum of its proper divisors (18779).

543721 is a wasteful number, since it uses less digits than its factorization.

543721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18778.

The product of its digits is 840, while the sum is 22.

The square root of 543721 is about 737.3743960838. The cubic root of 543721 is about 81.6191439929.

The spelling of 543721 in words is "five hundred forty-three thousand, seven hundred twenty-one".