243129 has 4 divisors (see below), whose sum is σ = 324176. Its totient is φ = 162084.

The previous prime is 243121. The next prime is 243137. The reversal of 243129 is 921342.

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.

It is an interprime number because it is at equal distance from previous prime (243121) and next prime (243137).

It is not a de Polignac number, because 243129 - 2³ = 243121 is a prime.

It is a super-2 number, since 2×243129² = 118223421282, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243121) 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, 40519 + ... + 40524.

It is an arithmetic number, because the mean of its divisors is an integer number (81044).

2²⁴³¹²⁹ is an apocalyptic number.

It is an amenable number.

243129 is a deficient number, since it is larger than the sum of its proper divisors (81047).

243129 is an equidigital number, since it uses as much as digits as its factorization.

243129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81046.

The product of its digits is 432, while the sum is 21.

The square root of 243129 is about 493.0811292272. The cubic root of 243129 is about 62.4135551584.

The spelling of 243129 in words is "two hundred forty-three thousand, one hundred twenty-nine".