518189989 has 4 divisors (see below), whose sum is σ = 525288556. Its totient is φ = 511091424.

The previous prime is 518189981. The next prime is 518190011. The reversal of 518189989 is 989981815.

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

It can be written as a sum of positive squares in 2 ways, for example, as 159390625 + 358799364 = 12625^2 + 18942^2 .

It is a cyclic number.

It is not a de Polignac number, because 518189989 - 2³ = 518189981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (518189981) 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, 3549174 + ... + 3549319.

It is an arithmetic number, because the mean of its divisors is an integer number (131322139).

Almost surely, 2^518189989 is an apocalyptic number.

It is an amenable number.

518189989 is a deficient number, since it is larger than the sum of its proper divisors (7098567).

518189989 is an equidigital number, since it uses as much as digits as its factorization.

518189989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7098566.

The product of its digits is 1866240, while the sum is 58.

The square root of 518189989 is about 22763.7867895480. The cubic root of 518189989 is about 803.2110468329.

The spelling of 518189989 in words is "five hundred eighteen million, one hundred eighty-nine thousand, nine hundred eighty-nine".