243021031 has 4 divisors (see below), whose sum is σ = 265113864. Its totient is φ = 220928200.

The previous prime is 243021029. The next prime is 243021041. The reversal of 243021031 is 130120342.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 243021031 - 2¹ = 243021029 is a prime.

It is a super-2 number, since 2×243021031² = 118118443016605922, 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 = 243020996 and 243021014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243021041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11046400 + ... + 11046421.

It is an arithmetic number, because the mean of its divisors is an integer number (66278466).

Almost surely, 2^243021031 is an apocalyptic number.

243021031 is a deficient number, since it is larger than the sum of its proper divisors (22092833).

243021031 is a wasteful number, since it uses less digits than its factorization.

243021031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22092832.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 243021031 is about 15589.1318231645. The cubic root of 243021031 is about 624.0431489653.

Adding to 243021031 its reverse (130120342), we get a palindrome (373141373).

The spelling of 243021031 in words is "two hundred forty-three million, twenty-one thousand, thirty-one".