1989437760 has 140 divisors (see below), whose sum is σ = 7076872308. Its totient is φ = 530509824.

The previous prime is 1989437743. The next prime is 1989437773. The reversal of 1989437760 is 677349891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 281434176 + 1708003584 = 16776^2 + 41328^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 1989437697 and 1989437706.

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 12457 + ... + 64296.

Almost surely, 2^1989437760 is an apocalyptic number.

1989437760 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 1989437760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3538436154).

1989437760 is an abundant number, since it is smaller than the sum of its proper divisors (5087434548).

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

1989437760 is an equidigital number, since it uses as much as digits as its factorization.

1989437760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76782 (or 76763 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The square root of 1989437760 is about 44603.1137926491. The cubic root of 1989437760 is about 1257.6992025934.

The spelling of 1989437760 in words is "one billion, nine hundred eighty-nine million, four hundred thirty-seven thousand, seven hundred sixty".