8647840261 has 2 divisors, whose sum is σ = 8647840262. Its totient is φ = 8647840260.

The previous prime is 8647840231. The next prime is 8647840277. The reversal of 8647840261 is 1620487468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8259356161 + 388484100 = 90881^2 + 19710^2 .

It is a cyclic number.

It is not a de Polignac number, because 8647840261 - 2³³ = 57905669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8647840231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4323920130 + 4323920131.

It is an arithmetic number, because the mean of its divisors is an integer number (4323920131).

Almost surely, 2^8647840261 is an apocalyptic number.

It is an amenable number.

8647840261 is a deficient number, since it is larger than the sum of its proper divisors (1).

8647840261 is an equidigital number, since it uses as much as digits as its factorization.

8647840261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 516096, while the sum is 46.

The square root of 8647840261 is about 92993.7646350550. The cubic root of 8647840261 is about 2052.5916269627.

The spelling of 8647840261 in words is "eight billion, six hundred forty-seven million, eight hundred forty thousand, two hundred sixty-one".