8121856241 has 2 divisors, whose sum is σ = 8121856242. Its totient is φ = 8121856240.

The previous prime is 8121856231. The next prime is 8121856277. The reversal of 8121856241 is 1426581218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7898054641 + 223801600 = 88871^2 + 14960^2 .

It is a cyclic number.

It is not a de Polignac number, because 8121856241 - 2³⁰ = 7048114417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 8121856195 and 8121856204.

It is not a weakly prime, because it can be changed into another prime (8121856231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4060928120 + 4060928121.

It is an arithmetic number, because the mean of its divisors is an integer number (4060928121).

Almost surely, 2^8121856241 is an apocalyptic number.

It is an amenable number.

8121856241 is a deficient number, since it is larger than the sum of its proper divisors (1).

8121856241 is an equidigital number, since it uses as much as digits as its factorization.

8121856241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30720, while the sum is 38.

The square root of 8121856241 is about 90121.3417620932. The cubic root of 8121856241 is about 2010.1035598400.

The spelling of 8121856241 in words is "eight billion, one hundred twenty-one million, eight hundred fifty-six thousand, two hundred forty-one".