999959897 has 2 divisors, whose sum is σ = 999959898. Its totient is φ = 999959896.

The previous prime is 999959879. The next prime is 999959903. The reversal of 999959897 is 798959999.

Together with previous prime (999959879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 616230976 + 383728921 = 24824^2 + 19589^2 .

It is a cyclic number.

It is not a de Polignac number, because 999959897 - 2¹⁰ = 999958873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (999959867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499979948 + 499979949.

It is an arithmetic number, because the mean of its divisors is an integer number (499979949).

Almost surely, 2^999959897 is an apocalyptic number.

It is an amenable number.

999959897 is a deficient number, since it is larger than the sum of its proper divisors (1).

999959897 is an equidigital number, since it uses as much as digits as its factorization.

999959897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 148803480, while the sum is 74.

The square root of 999959897 is about 31622.1425112215. The cubic root of 999959897 is about 999.9866321546.

It can be divided in two parts, 9999 and 59897, that added together give a palindrome (69896).

The spelling of 999959897 in words is "nine hundred ninety-nine million, nine hundred fifty-nine thousand, eight hundred ninety-seven".