115240240021 has 2 divisors, whose sum is σ = 115240240022. Its totient is φ = 115240240020.

The previous prime is 115240240019. The next prime is 115240240097. The reversal of 115240240021 is 120042042511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64320060996 + 50920179025 = 253614^2 + 225655^2 .

It is a cyclic number.

It is not a de Polignac number, because 115240240021 - 2¹ = 115240240019 is a prime.

Together with 115240240019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 115240239974 and 115240240001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (115240241021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57620120010 + 57620120011.

It is an arithmetic number, because the mean of its divisors is an integer number (57620120011).

Almost surely, 2^115240240021 is an apocalyptic number.

It is an amenable number.

115240240021 is a deficient number, since it is larger than the sum of its proper divisors (1).

115240240021 is an equidigital number, since it uses as much as digits as its factorization.

115240240021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 22.

Adding to 115240240021 its reverse (120042042511), we get a palindrome (235282282532).

The spelling of 115240240021 in words is "one hundred fifteen billion, two hundred forty million, two hundred forty thousand, twenty-one".