243115220281 has 2 divisors, whose sum is σ = 243115220282. Its totient is φ = 243115220280.

The previous prime is 243115220239. The next prime is 243115220357. The reversal of 243115220281 is 182022511342.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 239032010281 + 4083210000 = 488909^2 + 63900^2 .

It is a cyclic number.

It is not a de Polignac number, because 243115220281 - 2²³ = 243106831673 is a prime.

It is a super-2 number, since 2×243115220281² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243115220981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121557610140 + 121557610141.

It is an arithmetic number, because the mean of its divisors is an integer number (121557610141).

Almost surely, 2^243115220281 is an apocalyptic number.

It is an amenable number.

243115220281 is a deficient number, since it is larger than the sum of its proper divisors (1).

243115220281 is an equidigital number, since it uses as much as digits as its factorization.

243115220281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7680, while the sum is 31.

The spelling of 243115220281 in words is "two hundred forty-three billion, one hundred fifteen million, two hundred twenty thousand, two hundred eighty-one".