545561 has 4 divisors (see below), whose sum is σ = 549072. Its totient is φ = 542052.

The previous prime is 545551. The next prime is 545579. The reversal of 545561 is 165545.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 545561 - 2⁶ = 545497 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 545561.

It is not an unprimeable number, because it can be changed into a prime (545521) 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, 1511 + ... + 1836.

It is an arithmetic number, because the mean of its divisors is an integer number (137268).

2⁵⁴⁵⁵⁶¹ is an apocalyptic number.

It is an amenable number.

545561 is a deficient number, since it is larger than the sum of its proper divisors (3511).

545561 is a wasteful number, since it uses less digits than its factorization.

545561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3510.

The product of its digits is 3000, while the sum is 26.

The square root of 545561 is about 738.6210124279. The cubic root of 545561 is about 81.7111091344.

The spelling of 545561 in words is "five hundred forty-five thousand, five hundred sixty-one".