243624281 has 4 divisors (see below), whose sum is σ = 243688500. Its totient is φ = 243560064.

The previous prime is 243624253. The next prime is 243624299. The reversal of 243624281 is 182426342.

243624281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 171374281 + 72250000 = 13091^2 + 8500^2 .

It is a cyclic number.

It is not a de Polignac number, because 243624281 - 2¹⁸ = 243362137 is a prime.

It is a super-2 number, since 2×243624281² = 118705580585533922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243624881) 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, 26036 + ... + 34133.

It is an arithmetic number, because the mean of its divisors is an integer number (60922125).

Almost surely, 2^243624281 is an apocalyptic number.

It is an amenable number.

243624281 is a deficient number, since it is larger than the sum of its proper divisors (64219).

243624281 is an equidigital number, since it uses as much as digits as its factorization.

243624281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64218.

The product of its digits is 18432, while the sum is 32.

The square root of 243624281 is about 15608.4682464360. The cubic root of 243624281 is about 624.5590754634.

The spelling of 243624281 in words is "two hundred forty-three million, six hundred twenty-four thousand, two hundred eighty-one".