549681 has 8 divisors (see below), whose sum is σ = 799584. Its totient is φ = 333120.

The previous prime is 549667. The next prime is 549683. The reversal of 549681 is 186945.

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

It is not a de Polignac number, because 549681 - 2⁵ = 549649 is a prime.

It is a super-2 number, since 2×549681² = 604298403522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 16657 = 549681 / (5 + 4 + 9 + 6 + 8 + 1).

It is a Curzon number.

It is a nialpdrome in base 16.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 549681.

It is not an unprimeable number, because it can be changed into a prime (549683) 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, 8296 + ... + 8361.

It is an arithmetic number, because the mean of its divisors is an integer number (99948).

2⁵⁴⁹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

549681 is a deficient number, since it is larger than the sum of its proper divisors (249903).

549681 is a wasteful number, since it uses less digits than its factorization.

549681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16671.

The product of its digits is 8640, while the sum is 33.

The square root of 549681 is about 741.4047477593. The cubic root of 549681 is about 81.9162837854.

The spelling of 549681 in words is "five hundred forty-nine thousand, six hundred eighty-one".