243243503131 has 4 divisors (see below), whose sum is σ = 243270416664. Its totient is φ = 243216589600.

The previous prime is 243243503099. The next prime is 243243503183. The reversal of 243243503131 is 131305342342.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 131305342342 = 2 ⋅65652671171.

It is a cyclic number.

It is not a de Polignac number, because 243243503131 - 2⁵ = 243243503099 is a prime.

It is a super-2 number, since 2×243243503131² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243243503093 and 243243503102.

It is not an unprimeable number, because it can be changed into a prime (243243503731) 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, 13443205 + ... + 13461286.

It is an arithmetic number, because the mean of its divisors is an integer number (60817604166).

Almost surely, 2^243243503131 is an apocalyptic number.

243243503131 is a deficient number, since it is larger than the sum of its proper divisors (26913533).

243243503131 is an equidigital number, since it uses as much as digits as its factorization.

243243503131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26913532.

The product of its (nonzero) digits is 25920, while the sum is 31.

Adding to 243243503131 its reverse (131305342342), we get a palindrome (374548845473).

The spelling of 243243503131 in words is "two hundred forty-three billion, two hundred forty-three million, five hundred three thousand, one hundred thirty-one".