818989 has 8 divisors (see below), whose sum is σ = 875520. Its totient is φ = 764400.

The previous prime is 818977. The next prime is 818999. The reversal of 818989 is 989818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 818989 - 2¹¹ = 816941 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (818959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 444 + ... + 1354.

It is an arithmetic number, because the mean of its divisors is an integer number (109440).

2⁸¹⁸⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

818989 is a deficient number, since it is larger than the sum of its proper divisors (56531).

818989 is a wasteful number, since it uses less digits than its factorization.

818989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971.

The product of its digits is 41472, while the sum is 43.

The square root of 818989 is about 904.9801102787. The cubic root of 818989 is about 93.5605334988.

The spelling of 818989 in words is "eight hundred eighteen thousand, nine hundred eighty-nine".