998499505897 has 4 divisors (see below), whose sum is σ = 998793965056. Its totient is φ = 998205046740.

The previous prime is 998499505891. The next prime is 998499505903. The reversal of 998499505897 is 798505994899.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (998499505891) and next prime (998499505903).

It is a cyclic number.

It is not a de Polignac number, because 998499505897 - 2²³ = 998491117289 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 998499505897.

It is not an unprimeable number, because it can be changed into a prime (998499505891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147224493 + ... + 147231274.

It is an arithmetic number, because the mean of its divisors is an integer number (249698491264).

Almost surely, 2^998499505897 is an apocalyptic number.

It is an amenable number.

998499505897 is a deficient number, since it is larger than the sum of its proper divisors (294459159).

998499505897 is a wasteful number, since it uses less digits than its factorization.

998499505897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294459158.

The product of its (nonzero) digits is 2645395200, while the sum is 82.

The spelling of 998499505897 in words is "nine hundred ninety-eight billion, four hundred ninety-nine million, five hundred five thousand, eight hundred ninety-seven".