243664231 has 4 divisors (see below), whose sum is σ = 254258352. Its totient is φ = 233070112.

The previous prime is 243664229. The next prime is 243664241. The reversal of 243664231 is 132466342.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132466342 = 2 ⋅66233171.

It is a cyclic number.

It is not a de Polignac number, because 243664231 - 2¹ = 243664229 is a prime.

It is a super-2 number, since 2×243664231² = 118744514937642722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243664193 and 243664202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243664241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5297026 + ... + 5297071.

It is an arithmetic number, because the mean of its divisors is an integer number (63564588).

Almost surely, 2^243664231 is an apocalyptic number.

243664231 is a deficient number, since it is larger than the sum of its proper divisors (10594121).

243664231 is a wasteful number, since it uses less digits than its factorization.

243664231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10594120.

The product of its digits is 20736, while the sum is 31.

The square root of 243664231 is about 15609.7479479971. The cubic root of 243664231 is about 624.5932124156.

The spelling of 243664231 in words is "two hundred forty-three million, six hundred sixty-four thousand, two hundred thirty-one".