243857121 has 16 divisors (see below), whose sum is σ = 338169600. Its totient is φ = 156169728.

The previous prime is 243857113. The next prime is 243857177. The reversal of 243857121 is 121758342.

It is not a de Polignac number, because 243857121 - 2³ = 243857113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (243857111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5136 + ... + 22673.

It is an arithmetic number, because the mean of its divisors is an integer number (21135600).

Almost surely, 2^243857121 is an apocalyptic number.

It is an amenable number.

243857121 is a deficient number, since it is larger than the sum of its proper divisors (94312479).

243857121 is a wasteful number, since it uses less digits than its factorization.

243857121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27928.

The product of its digits is 13440, while the sum is 33.

The square root of 243857121 is about 15615.9252367575. The cubic root of 243857121 is about 624.7579828831.

The spelling of 243857121 in words is "two hundred forty-three million, eight hundred fifty-seven thousand, one hundred twenty-one".