243257137 has 2 divisors, whose sum is σ = 243257138. Its totient is φ = 243257136.

The previous prime is 243257123. The next prime is 243257159. The reversal of 243257137 is 731752342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122235136 + 121022001 = 11056^2 + 11001^2 .

It is a cyclic number.

It is not a de Polignac number, because 243257137 - 2¹⁵ = 243224369 is a prime.

It is not a weakly prime, because it can be changed into another prime (243257107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121628568 + 121628569.

It is an arithmetic number, because the mean of its divisors is an integer number (121628569).

Almost surely, 2^243257137 is an apocalyptic number.

It is an amenable number.

243257137 is a deficient number, since it is larger than the sum of its proper divisors (1).

243257137 is an equidigital number, since it uses as much as digits as its factorization.

243257137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35280, while the sum is 34.

The square root of 243257137 is about 15596.7027605196. The cubic root of 243257137 is about 624.2451789994.

The spelling of 243257137 in words is "two hundred forty-three million, two hundred fifty-seven thousand, one hundred thirty-seven".