243990757 has 2 divisors, whose sum is σ = 243990758. Its totient is φ = 243990756.

The previous prime is 243990727. The next prime is 243990787. The reversal of 243990757 is 757099342.

It is a balanced prime because it is at equal distance from previous prime (243990727) and next prime (243990787).

It can be written as a sum of positive squares in only one way, i.e., 218123361 + 25867396 = 14769^2 + 5086^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243990757 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243990707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121995378 + 121995379.

It is an arithmetic number, because the mean of its divisors is an integer number (121995379).

Almost surely, 2^243990757 is an apocalyptic number.

It is an amenable number.

243990757 is a deficient number, since it is larger than the sum of its proper divisors (1).

243990757 is an equidigital number, since it uses as much as digits as its factorization.

243990757 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 476280, while the sum is 46.

The square root of 243990757 is about 15620.2034877911. The cubic root of 243990757 is about 624.8720864628.

The spelling of 243990757 in words is "two hundred forty-three million, nine hundred ninety thousand, seven hundred fifty-seven".