539981 has 8 divisors (see below), whose sum is σ = 590520. Its totient is φ = 490752.

The previous prime is 539947. The next prime is 539993. The reversal of 539981 is 189935.

539981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1225 + 538756 = 35^2 + 734^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 539981 - 2¹⁴ = 523597 is a prime.

It is a super-2 number, since 2×539981² = 583158960722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (539921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 665 + ... + 1233.

It is an arithmetic number, because the mean of its divisors is an integer number (73815).

2⁵³⁹⁹⁸¹ is an apocalyptic number.

It is an amenable number.

539981 is a deficient number, since it is larger than the sum of its proper divisors (50539).

539981 is a wasteful number, since it uses less digits than its factorization.

539981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655.

The product of its digits is 9720, while the sum is 35.

The square root of 539981 is about 734.8339948587. The cubic root of 539981 is about 81.4315734138.

The spelling of 539981 in words is "five hundred thirty-nine thousand, nine hundred eighty-one".