243326021 has 8 divisors (see below), whose sum is σ = 253966104. Its totient is φ = 232910080.

The previous prime is 243325997. The next prime is 243326053. The reversal of 243326021 is 120623342.

It can be written as a sum of positive squares in 4 ways, for example, as 4468996 + 238857025 = 2114^2 + 15455^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 243326021 - 2¹⁴ = 243309637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243326221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53816 + ... + 58161.

It is an arithmetic number, because the mean of its divisors is an integer number (31745763).

Almost surely, 2^243326021 is an apocalyptic number.

It is an amenable number.

243326021 is a deficient number, since it is larger than the sum of its proper divisors (10640083).

243326021 is a wasteful number, since it uses less digits than its factorization.

243326021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112071.

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 243326021 is about 15598.9108914693. The cubic root of 243326021 is about 624.3040966907.

Adding to 243326021 its reverse (120623342), we get a palindrome (363949363).

The spelling of 243326021 in words is "two hundred forty-three million, three hundred twenty-six thousand, twenty-one".