243998947 has 2 divisors, whose sum is σ = 243998948. Its totient is φ = 243998946.

The previous prime is 243998933. The next prime is 243998987. The reversal of 243998947 is 749899342.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 243998947 - 2¹¹ = 243996899 is a prime.

It is a super-2 number, since 2×243998947² = 119070972274217618, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243998987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121999473 + 121999474.

It is an arithmetic number, because the mean of its divisors is an integer number (121999474).

Almost surely, 2^243998947 is an apocalyptic number.

243998947 is a deficient number, since it is larger than the sum of its proper divisors (1).

243998947 is an equidigital number, since it uses as much as digits as its factorization.

243998947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3919104, while the sum is 55.

The square root of 243998947 is about 15620.4656460683. The cubic root of 243998947 is about 624.8790780461.

The spelling of 243998947 in words is "two hundred forty-three million, nine hundred ninety-eight thousand, nine hundred forty-seven".