545661 has 12 divisors (see below), whose sum is σ = 829920. Its totient is φ = 344520.

The previous prime is 545651. The next prime is 545663. The reversal of 545661 is 166545.

It is a happy number.

It is not a de Polignac number, because 545661 - 2⁷ = 545533 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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 545661.

It is not an unprimeable number, because it can be changed into a prime (545663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1425 + ... + 1766.

It is an arithmetic number, because the mean of its divisors is an integer number (69160).

2⁵⁴⁵⁶⁶¹ is an apocalyptic number.

It is an amenable number.

545661 is a deficient number, since it is larger than the sum of its proper divisors (284259).

545661 is a wasteful number, since it uses less digits than its factorization.

545661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3216 (or 3213 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 545661 is about 738.6887030407. The cubic root of 545661 is about 81.7161013117.

The spelling of 545661 in words is "five hundred forty-five thousand, six hundred sixty-one".