243755257 has 2 divisors, whose sum is σ = 243755258. Its totient is φ = 243755256.

The previous prime is 243755243. The next prime is 243755273. The reversal of 243755257 is 752557342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 151191616 + 92563641 = 12296^2 + 9621^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243755257 is a prime.

It is not a weakly prime, because it can be changed into another prime (243755227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121877628 + 121877629.

It is an arithmetic number, because the mean of its divisors is an integer number (121877629).

Almost surely, 2^243755257 is an apocalyptic number.

It is an amenable number.

243755257 is a deficient number, since it is larger than the sum of its proper divisors (1).

243755257 is an equidigital number, since it uses as much as digits as its factorization.

243755257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 294000, while the sum is 40.

The square root of 243755257 is about 15612.6633538292. The cubic root of 243755257 is about 624.6709794632.

The spelling of 243755257 in words is "two hundred forty-three million, seven hundred fifty-five thousand, two hundred fifty-seven".