999997697 has 2 divisors, whose sum is σ = 999997698.
Its totient is φ = 999997696.
The previous prime is 999997679. The next prime is 999997717. The reversal of 999997697 is 796799999.
Together with previous prime (999997679) it forms an Ormiston pair, because they use the same digits, order apart.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 891858496 + 108139201 = 29864^2 + 10399^2
It is a cyclic number.
It is not a de Polignac number, because 999997697 - 214 = 999981313 is a prime.
It is a Chen prime.
It is not a weakly prime, because it can be changed into another prime (999997627) 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, 499998848 + 499998849.
It is an arithmetic number, because the mean of its divisors is an integer number (499998849).
Almost surely, 2999997697 is an apocalyptic number.
It is an amenable number.
999997697 is a deficient number, since it is larger than the sum of its proper divisors (1).
999997697 is an equidigital number, since it uses as much as digits as its factorization.
999997697 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 156243654, while the sum is 74.
The square root of 999997697 is about 31622.7401880356.
The cubic root of 999997697 is about 999.9992323327.
Note that the first 3 decimals are identical.
The spelling of 999997697 in words is "nine hundred ninety-nine million, nine hundred ninety-seven thousand, six hundred ninety-seven".