243021021 has 8 divisors (see below), whose sum is σ = 324121824. Its totient is φ = 161967120.

The previous prime is 243021017. The next prime is 243021029. The reversal of 243021021 is 120120342.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 243021021 - 2² = 243021017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243021029) 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 7 ways as a sum of consecutive naturals, for example, 3015 + ... + 22251.

It is an arithmetic number, because the mean of its divisors is an integer number (40515228).

Almost surely, 2^243021021 is an apocalyptic number.

It is an amenable number.

243021021 is a deficient number, since it is larger than the sum of its proper divisors (81100803).

243021021 is a wasteful number, since it uses less digits than its factorization.

243021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23451.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 243021021 is about 15589.1315024282. The cubic root of 243021021 is about 624.0431404058.

Adding to 243021021 its reverse (120120342), we get a palindrome (363141363).

The spelling of 243021021 in words is "two hundred forty-three million, twenty-one thousand, twenty-one".