999823142897 has 2 divisors, whose sum is σ = 999823142898. Its totient is φ = 999823142896.

The previous prime is 999823142893. The next prime is 999823142917. The reversal of 999823142897 is 798241328999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 636299763856 + 363523379041 = 797684^2 + 602929^2 .

It is an emirp because it is prime and its reverse (798241328999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999823142897 - 2² = 999823142893 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 999823142897.

It is not a weakly prime, because it can be changed into another prime (999823142893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499911571448 + 499911571449.

It is an arithmetic number, because the mean of its divisors is an integer number (499911571449).

Almost surely, 2^999823142897 is an apocalyptic number.

It is an amenable number.

999823142897 is a deficient number, since it is larger than the sum of its proper divisors (1).

999823142897 is an equidigital number, since it uses as much as digits as its factorization.

999823142897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141087744, while the sum is 71.

The spelling of 999823142897 in words is "nine hundred ninety-nine billion, eight hundred twenty-three million, one hundred forty-two thousand, eight hundred ninety-seven".