999489815863841 has 4 divisors (see below), whose sum is σ = 999489888874884. Its totient is φ = 999489742852800.

The previous prime is 999489815863817. The next prime is 999489815863849. The reversal of 999489815863841 is 148368518984999.

999489815863841 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 119983543690000 + 879506272173841 = 10953700^2 + 29656471^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999489815863841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999489815863849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9126380 + ... + 45631901.

It is an arithmetic number, because the mean of its divisors is an integer number (249872472218721).

It is a Poulet number, since it divides 2^{999489815863840}-1.

Almost surely, 2^{999489815863841} is an apocalyptic number.

999489815863841 is the 18252761-st octagonal number.

It is an amenable number.

999489815863841 is a deficient number, since it is larger than the sum of its proper divisors (73011043).

999489815863841 is a wasteful number, since it uses less digits than its factorization.

999489815863841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73011042.

The product of its digits is 38698352640, while the sum is 92.

The spelling of 999489815863841 in words is "nine hundred ninety-nine trillion, four hundred eighty-nine billion, eight hundred fifteen million, eight hundred sixty-three thousand, eight hundred forty-one".