243439969 has 2 divisors, whose sum is σ = 243439970. Its totient is φ = 243439968.

The previous prime is 243439967. The next prime is 243440033. The reversal of 243439969 is 969934342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 237622225 + 5817744 = 15415^2 + 2412^2 .

It is a cyclic number.

It is not a de Polignac number, because 243439969 - 2¹ = 243439967 is a prime.

It is a super-2 number, since 2×243439969² = 118526037013441922, which contains 22 as substring.

Together with 243439967, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (243439967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121719984 + 121719985.

It is an arithmetic number, because the mean of its divisors is an integer number (121719985).

Almost surely, 2^243439969 is an apocalyptic number.

It is an amenable number.

243439969 is a deficient number, since it is larger than the sum of its proper divisors (1).

243439969 is an equidigital number, since it uses as much as digits as its factorization.

243439969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1259712, while the sum is 49.

The square root of 243439969 is about 15602.5628984472. The cubic root of 243439969 is about 624.4015340044.

The spelling of 243439969 in words is "two hundred forty-three million, four hundred thirty-nine thousand, nine hundred sixty-nine".