145809 has 12 divisors (see below), whose sum is σ = 223236. Its totient is φ = 91392.

The previous prime is 145807. The next prime is 145819. The reversal of 145809 is 908541.

It can be written as a sum of positive squares in 2 ways, for example, as 88209 + 57600 = 297^2 + 240^2 .

It is not a de Polignac number, because 145809 - 2¹ = 145807 is a prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 145809.

It is not an unprimeable number, because it can be changed into a prime (145807) 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, 324 + ... + 629.

It is an arithmetic number, because the mean of its divisors is an integer number (18603).

2¹⁴⁵⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

145809 is a deficient number, since it is larger than the sum of its proper divisors (77427).

145809 is a wasteful number, since it uses less digits than its factorization.

145809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 976 (or 973 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 145809 is about 381.8494467719. The cubic root of 145809 is about 52.6334022351.

The spelling of 145809 in words is "one hundred forty-five thousand, eight hundred nine".