145309 has 4 divisors (see below), whose sum is σ = 146080. Its totient is φ = 144540.

The previous prime is 145307. The next prime is 145349. The reversal of 145309 is 903541.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 145309 - 2¹ = 145307 is a prime.

It is a super-2 number, since 2×145309² = 42229410962, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 145309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145303) 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 3 ways as a sum of consecutive naturals, for example, 112 + ... + 550.

It is an arithmetic number, because the mean of its divisors is an integer number (36520).

2¹⁴⁵³⁰⁹ is an apocalyptic number.

It is an amenable number.

145309 is a deficient number, since it is larger than the sum of its proper divisors (771).

145309 is an equidigital number, since it uses as much as digits as its factorization.

145309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 770.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 145309 is about 381.1941762409. The cubic root of 145309 is about 52.5731708369.

It can be divided in two parts, 145 and 309, that added together give a palindrome (454).

The spelling of 145309 in words is "one hundred forty-five thousand, three hundred nine".