243220131 has 32 divisors (see below), whose sum is σ = 449241600. Its totient is φ = 126347040.

The previous prime is 243220099. The next prime is 243220189. The reversal of 243220131 is 131022342.

243220131 is a `hidden beast` number, since 2 + 432 + 201 + 31 = 666.

It is not a de Polignac number, because 243220131 - 2⁵ = 243220099 is a prime.

It is a super-2 number, since 2×243220131² = 118312064247314322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (243220231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56416 + ... + 60573.

It is an arithmetic number, because the mean of its divisors is an integer number (14038800).

Almost surely, 2^243220131 is an apocalyptic number.

243220131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

243220131 is a deficient number, since it is larger than the sum of its proper divisors (206021469).

243220131 is a wasteful number, since it uses less digits than its factorization.

243220131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117016 (or 117010 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 243220131 is about 15595.5163749072. The cubic root of 243220131 is about 624.2135225269.

Adding to 243220131 its reverse (131022342), we get a palindrome (374242473).

The spelling of 243220131 in words is "two hundred forty-three million, two hundred twenty thousand, one hundred thirty-one".