243644441 has 2 divisors, whose sum is σ = 243644442. Its totient is φ = 243644440.

The previous prime is 243644419. The next prime is 243644449. The reversal of 243644441 is 144446342.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151388416 + 92256025 = 12304^2 + 9605^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243644441 is a prime.

It is a super-2 number, since 2×243644441² = 118725227260404962, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 243644398 and 243644407.

It is not a weakly prime, because it can be changed into another prime (243644449) 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, 121822220 + 121822221.

It is an arithmetic number, because the mean of its divisors is an integer number (121822221).

Almost surely, 2^243644441 is an apocalyptic number.

It is an amenable number.

243644441 is a deficient number, since it is larger than the sum of its proper divisors (1).

243644441 is an equidigital number, since it uses as much as digits as its factorization.

243644441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36864, while the sum is 32.

The square root of 243644441 is about 15609.1140363571. The cubic root of 243644441 is about 624.5763024869.

The spelling of 243644441 in words is "two hundred forty-three million, six hundred forty-four thousand, four hundred forty-one".