1989117618 has 8 divisors (see below), whose sum is σ = 3978235248. Its totient is φ = 663039204.

The previous prime is 1989117601. The next prime is 1989117629. The reversal of 1989117618 is 8167119891.

It is a happy number.

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

1989117618 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165759796 + ... + 165759807.

It is an arithmetic number, because the mean of its divisors is an integer number (497279406).

Almost surely, 2^1989117618 is an apocalyptic number.

1989117618 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1989117618 is a wasteful number, since it uses less digits than its factorization.

1989117618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331519608.

The product of its digits is 217728, while the sum is 51.

The square root of 1989117618 is about 44599.5248629400. The cubic root of 1989117618 is about 1257.6317356360.

The spelling of 1989117618 in words is "one billion, nine hundred eighty-nine million, one hundred seventeen thousand, six hundred eighteen".