545809 has 12 divisors (see below), whose sum is σ = 627120. Its totient is φ = 470960.

The previous prime is 545791. The next prime is 545827. The reversal of 545809 is 908545.

It is an interprime number because it is at equal distance from previous prime (545791) and next prime (545827).

It is not a de Polignac number, because 545809 - 2¹⁵ = 513041 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (545899) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9222 + ... + 9280.

It is an arithmetic number, because the mean of its divisors is an integer number (52260).

2⁵⁴⁵⁸⁰⁹ is an apocalyptic number.

545809 is a gapful number since it is divisible by the number (59) formed by its first and last digit.

It is an amenable number.

545809 is a deficient number, since it is larger than the sum of its proper divisors (81311).

545809 is a wasteful number, since it uses less digits than its factorization.

545809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 545809 is about 738.7888737657. The cubic root of 545809 is about 81.7234886149.

The spelling of 545809 in words is "five hundred forty-five thousand, eight hundred nine".