9000009081961 has 2 divisors, whose sum is σ = 9000009081962. Its totient is φ = 9000009081960.

The previous prime is 9000009081859. The next prime is 9000009081991. The reversal of 9000009081961 is 1691809000009.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8704600526736 + 295408555225 = 2950356^2 + 543515^2 .

It is a cyclic number.

It is not a de Polignac number, because 9000009081961 - 2⁹ = 9000009081449 is a prime.

It is not a weakly prime, because it can be changed into another prime (9000009081991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4500004540980 + 4500004540981.

It is an arithmetic number, because the mean of its divisors is an integer number (4500004540981).

Almost surely, 2^{9000009081961} is an apocalyptic number.

It is an amenable number.

9000009081961 is a deficient number, since it is larger than the sum of its proper divisors (1).

9000009081961 is an equidigital number, since it uses as much as digits as its factorization.

9000009081961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 43.

The spelling of 9000009081961 in words is "nine trillion, nine million, eighty-one thousand, nine hundred sixty-one".