999989218 has 4 divisors (see below), whose sum is σ = 1499983830. Its totient is φ = 499994608.

The previous prime is 999989203. The next prime is 999989219. The reversal of 999989218 is 812989999.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 995591809 + 4397409 = 31553^2 + 2097^2 .

It is a super-2 number, since 2×999989218² = 1999956872232503048, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 999989218.

It is not an unprimeable number, because it can be changed into a prime (999989219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249997303 + ... + 249997306.

Almost surely, 2^999989218 is an apocalyptic number.

999989218 is a deficient number, since it is larger than the sum of its proper divisors (499994612).

999989218 is a wasteful number, since it uses less digits than its factorization.

999989218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499994611.

The product of its digits is 7558272, while the sum is 64.

The square root of 999989218 is about 31622.6061228356. The cubic root of 999989218 is about 999.9964059871.

The spelling of 999989218 in words is "nine hundred ninety-nine million, nine hundred eighty-nine thousand, two hundred eighteen".