243452009981 has 2 divisors, whose sum is σ = 243452009982. Its totient is φ = 243452009980.

The previous prime is 243452009959. The next prime is 243452010019. The reversal of 243452009981 is 189900254342.

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., 193111908025 + 50340101956 = 439445^2 + 224366^2 .

It is a cyclic number.

It is not a de Polignac number, because 243452009981 - 2³⁴ = 226272140797 is a prime.

It is a super-2 number, since 2×243452009981² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243452009681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121726004990 + 121726004991.

It is an arithmetic number, because the mean of its divisors is an integer number (121726004991).

Almost surely, 2^243452009981 is an apocalyptic number.

It is an amenable number.

243452009981 is a deficient number, since it is larger than the sum of its proper divisors (1).

243452009981 is an equidigital number, since it uses as much as digits as its factorization.

243452009981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 622080, while the sum is 47.

The spelling of 243452009981 in words is "two hundred forty-three billion, four hundred fifty-two million, nine thousand, nine hundred eighty-one".