243251563 has 2 divisors, whose sum is σ = 243251564. Its totient is φ = 243251562.

The previous prime is 243251557. The next prime is 243251581. The reversal of 243251563 is 365152342.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243251563 is a prime.

It is not a weakly prime, because it can be changed into another prime (243251543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121625781 + 121625782.

It is an arithmetic number, because the mean of its divisors is an integer number (121625782).

Almost surely, 2^243251563 is an apocalyptic number.

243251563 is a deficient number, since it is larger than the sum of its proper divisors (1).

243251563 is an equidigital number, since it uses as much as digits as its factorization.

243251563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21600, while the sum is 31.

The square root of 243251563 is about 15596.5240678813. The cubic root of 243251563 is about 624.2404109732.

The spelling of 243251563 in words is "two hundred forty-three million, two hundred fifty-one thousand, five hundred sixty-three".