243121245109 has 2 divisors, whose sum is σ = 243121245110. Its totient is φ = 243121245108.

The previous prime is 243121245097. The next prime is 243121245181. The reversal of 243121245109 is 901542121342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125756762884 + 117364482225 = 354622^2 + 342585^2 .

It is a cyclic number.

It is not a de Polignac number, because 243121245109 - 2¹¹ = 243121243061 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243121245509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560622554 + 121560622555.

It is an arithmetic number, because the mean of its divisors is an integer number (121560622555).

Almost surely, 2^243121245109 is an apocalyptic number.

It is an amenable number.

243121245109 is a deficient number, since it is larger than the sum of its proper divisors (1).

243121245109 is an equidigital number, since it uses as much as digits as its factorization.

243121245109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 34.

The spelling of 243121245109 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred forty-five thousand, one hundred nine".