243042421 has 8 divisors (see below), whose sum is σ = 257629464. Its totient is φ = 228487680.

The previous prime is 243042419. The next prime is 243042431. The reversal of 243042421 is 124240342.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 155900196 + 87142225 = 12486^2 + 9335^2 .

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 243042421 - 2¹ = 243042419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243042392 and 243042401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243042431) 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, 8401 + ... + 23593.

It is an arithmetic number, because the mean of its divisors is an integer number (32203683).

Almost surely, 2^243042421 is an apocalyptic number.

It is an amenable number.

243042421 is a deficient number, since it is larger than the sum of its proper divisors (14587043).

243042421 is a wasteful number, since it uses less digits than its factorization.

243042421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16151.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 243042421 is about 15589.8178629514. The cubic root of 243042421 is about 624.0614572455.

Adding to 243042421 its reverse (124240342), we get a palindrome (367282763).

The spelling of 243042421 in words is "two hundred forty-three million, forty-two thousand, four hundred twenty-one".