1998545280 has 128 divisors (see below), whose sum is σ = 6506196480. Its totient is φ = 521582592.

The previous prime is 1998545273. The next prime is 1998545281. The reversal of 1998545280 is 825458991.

1998545280 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998545281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79167 + ... + 101313.

It is an arithmetic number, because the mean of its divisors is an integer number (50829660).

Almost surely, 2^1998545280 is an apocalyptic number.

1998545280 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 1998545280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3253098240).

1998545280 is an abundant number, since it is smaller than the sum of its proper divisors (4507651200).

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

1998545280 is a wasteful number, since it uses less digits than its factorization.

1998545280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22216 (or 22204 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 51.

The square root of 1998545280 is about 44705.0923273848. The cubic root of 1998545280 is about 1259.6155037439.

The spelling of 1998545280 in words is "one billion, nine hundred ninety-eight million, five hundred forty-five thousand, two hundred eighty".