8971499561 has 2 divisors, whose sum is σ = 8971499562. Its totient is φ = 8971499560.

The previous prime is 8971499521. The next prime is 8971499597. The reversal of 8971499561 is 1659941798.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8694443536 + 277056025 = 93244^2 + 16645^2 .

It is a cyclic number.

It is not a de Polignac number, because 8971499561 - 2⁶ = 8971499497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8971499561.

It is not a weakly prime, because it can be changed into another prime (8971499521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4485749780 + 4485749781.

It is an arithmetic number, because the mean of its divisors is an integer number (4485749781).

Almost surely, 2^8971499561 is an apocalyptic number.

It is an amenable number.

8971499561 is a deficient number, since it is larger than the sum of its proper divisors (1).

8971499561 is an equidigital number, since it uses as much as digits as its factorization.

8971499561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 59.

The square root of 8971499561 is about 94718.0001953166. Note that the first 3 decimals coincide. The cubic root of 8971499561 is about 2077.8858234141.

The spelling of 8971499561 in words is "eight billion, nine hundred seventy-one million, four hundred ninety-nine thousand, five hundred sixty-one".