142309 has 4 divisors (see below), whose sum is σ = 143820. Its totient is φ = 140800.

The previous prime is 142297. The next prime is 142319. The reversal of 142309 is 903241.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 65025 + 77284 = 255^2 + 278^2 .

It is a cyclic number.

It is not a de Polignac number, because 142309 - 2¹⁵ = 109541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (142319) 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, 604 + ... + 805.

It is an arithmetic number, because the mean of its divisors is an integer number (35955).

2¹⁴²³⁰⁹ is an apocalyptic number.

142309 is the 202-nd nonagonal number.

It is an amenable number.

142309 is a deficient number, since it is larger than the sum of its proper divisors (1511).

142309 is a wasteful number, since it uses less digits than its factorization.

142309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1510.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 142309 is about 377.2386512541. The cubic root of 142309 is about 52.2088494169.

The spelling of 142309 in words is "one hundred forty-two thousand, three hundred nine".