1989911000 has 256 divisors, whose sum is σ = 5950264320. Its totient is φ = 604800000.

The previous prime is 1989910999. The next prime is 1989911003. The reversal of 1989911000 is 1199891.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989911003) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 3310700 + ... + 3311300.

It is an arithmetic number, because the mean of its divisors is an integer number (23243220).

Almost surely, 2^1989911000 is an apocalyptic number.

1989911000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1989911000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2975132160).

1989911000 is an abundant number, since it is smaller than the sum of its proper divisors (3960353320).

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

1989911000 is a wasteful number, since it uses less digits than its factorization.

1989911000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 683 (or 669 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 38.

The square root of 1989911000 is about 44608.4184879939. The cubic root of 1989911000 is about 1257.7989202783.

It can be divided in two parts, 198991 and 1000, that added together give a palindrome (199991).

The spelling of 1989911000 in words is "one billion, nine hundred eighty-nine million, nine hundred eleven thousand".