999961289 has 2 divisors, whose sum is σ = 999961290. Its totient is φ = 999961288.

The previous prime is 999961273. The next prime is 999961357. The reversal of 999961289 is 982169999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 590101264 + 409860025 = 24292^2 + 20245^2 .

It is a cyclic number.

It is not a de Polignac number, because 999961289 - 2⁴ = 999961273 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (999961189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499980644 + 499980645.

It is an arithmetic number, because the mean of its divisors is an integer number (499980645).

Almost surely, 2^999961289 is an apocalyptic number.

It is an amenable number.

999961289 is a deficient number, since it is larger than the sum of its proper divisors (1).

999961289 is an equidigital number, since it uses as much as digits as its factorization.

999961289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5668704, while the sum is 62.

The square root of 999961289 is about 31622.1645211077. The cubic root of 999961289 is about 999.9870961668.

The spelling of 999961289 in words is "nine hundred ninety-nine million, nine hundred sixty-one thousand, two hundred eighty-nine".