1988888889 has 8 divisors (see below), whose sum is σ = 2855840512. Its totient is φ = 1223931600.

The previous prime is 1988888857. The next prime is 1988888899. The reversal of 1988888889 is 9888888891.

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

It is not a de Polignac number, because 1988888889 - 2⁵ = 1988888857 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1988888889.

It is not an unprimeable number, because it can be changed into a prime (1988888899) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25498537 + ... + 25498614.

It is an arithmetic number, because the mean of its divisors is an integer number (356980064).

Almost surely, 2^1988888889 is an apocalyptic number.

It is an amenable number.

1988888889 is a deficient number, since it is larger than the sum of its proper divisors (866951623).

1988888889 is a wasteful number, since it uses less digits than its factorization.

1988888889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50997167.

The product of its digits is 169869312, while the sum is 75.

The square root of 1988888889 is about 44596.9605354446. The cubic root of 1988888889 is about 1257.5835286868.

The spelling of 1988888889 in words is "one billion, nine hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred eighty-nine".