115221242161 has 2 divisors, whose sum is σ = 115221242162. Its totient is φ = 115221242160.

The previous prime is 115221242137. The next prime is 115221242209. The reversal of 115221242161 is 161242122511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 115148242225 + 72999936 = 339335^2 + 8544^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115221242161 is a prime.

It is not a weakly prime, because it can be changed into another prime (115221242561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57610621080 + 57610621081.

It is an arithmetic number, because the mean of its divisors is an integer number (57610621081).

Almost surely, 2^115221242161 is an apocalyptic number.

It is an amenable number.

115221242161 is a deficient number, since it is larger than the sum of its proper divisors (1).

115221242161 is an equidigital number, since it uses as much as digits as its factorization.

115221242161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 28.

Adding to 115221242161 its reverse (161242122511), we get a palindrome (276463364672).

The spelling of 115221242161 in words is "one hundred fifteen billion, two hundred twenty-one million, two hundred forty-two thousand, one hundred sixty-one".