145209 has 8 divisors (see below), whose sum is σ = 196000. Its totient is φ = 95616.

The previous prime is 145207. The next prime is 145213. The reversal of 145209 is 902541.

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

It is not a de Polignac number, because 145209 - 2¹ = 145207 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (145207) 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, 42 + ... + 540.

It is an arithmetic number, because the mean of its divisors is an integer number (24500).

2¹⁴⁵²⁰⁹ is an apocalyptic number.

It is an amenable number.

145209 is a deficient number, since it is larger than the sum of its proper divisors (50791).

145209 is an equidigital number, since it uses as much as digits as its factorization.

145209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 599.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 145209 is about 381.0629869195. The cubic root of 145209 is about 52.5611079834.

The spelling of 145209 in words is "one hundred forty-five thousand, two hundred nine".