998812817 has 12 divisors (see below), whose sum is σ = 1029569436. Its totient is φ = 968950080.

The previous prime is 998812813. The next prime is 998812831. The reversal of 998812817 is 718218899.

It is a happy number.

It is a Cunningham number, because it is equal to 31604²+1.

It can be written as a sum of positive squares in 6 ways, for example, as 4734976 + 994077841 = 2176^2 + 31529^2 .

It is not a de Polignac number, because 998812817 - 2² = 998812813 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (998812811) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 575483 + ... + 577215.

It is an arithmetic number, because the mean of its divisors is an integer number (85797453).

Almost surely, 2^998812817 is an apocalyptic number.

It is an amenable number.

998812817 is a deficient number, since it is larger than the sum of its proper divisors (30756619).

998812817 is a wasteful number, since it uses less digits than its factorization.

998812817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2228 (or 2191 counting only the distinct ones).

The product of its digits is 580608, while the sum is 53.

The square root of 998812817 is about 31604.0000158208. Note that the first 4 decimals coincide. The cubic root of 998812817 is about 999.6041156296.

The spelling of 998812817 in words is "nine hundred ninety-eight million, eight hundred twelve thousand, eight hundred seventeen".