243120717251 has 2 divisors, whose sum is σ = 243120717252. Its totient is φ = 243120717250.

The previous prime is 243120717233. The next prime is 243120717263. The reversal of 243120717251 is 152717021342.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243120717251 is a prime.

It is not a weakly prime, because it can be changed into another prime (243120717221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560358625 + 121560358626.

It is an arithmetic number, because the mean of its divisors is an integer number (121560358626).

Almost surely, 2^243120717251 is an apocalyptic number.

243120717251 is a deficient number, since it is larger than the sum of its proper divisors (1).

243120717251 is an equidigital number, since it uses as much as digits as its factorization.

243120717251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23520, while the sum is 35.

Adding to 243120717251 its reverse (152717021342), we get a palindrome (395837738593).

The spelling of 243120717251 in words is "two hundred forty-three billion, one hundred twenty million, seven hundred seventeen thousand, two hundred fifty-one".