8666961824401 has 2 divisors, whose sum is σ = 8666961824402. Its totient is φ = 8666961824400.

The previous prime is 8666961824377. The next prime is 8666961824441. The reversal of 8666961824401 is 1044281696668.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6450507846225 + 2216453978176 = 2539785^2 + 1488776^2 .

It is a cyclic number.

It is not a de Polignac number, because 8666961824401 - 2⁷ = 8666961824273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8666961824401.

It is not a weakly prime, because it can be changed into another prime (8666961824441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4333480912200 + 4333480912201.

It is an arithmetic number, because the mean of its divisors is an integer number (4333480912201).

Almost surely, 2^{8666961824401} is an apocalyptic number.

It is an amenable number.

8666961824401 is a deficient number, since it is larger than the sum of its proper divisors (1).

8666961824401 is an equidigital number, since it uses as much as digits as its factorization.

8666961824401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23887872, while the sum is 61.

The spelling of 8666961824401 in words is "eight trillion, six hundred sixty-six billion, nine hundred sixty-one million, eight hundred twenty-four thousand, four hundred one".