1981450800 has 360 divisors, whose sum is σ = 7993521120. Its totient is φ = 445132800.

The previous prime is 1981450799. The next prime is 1981450811. The reversal of 1981450800 is 80541891.

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-3 number, since 3×1981450800³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 71 ways as a sum of consecutive naturals, for example, 1536556 + ... + 1537844.

Almost surely, 2^1981450800 is an apocalyptic number.

1981450800 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 1981450800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3996760560).

1981450800 is an abundant number, since it is smaller than the sum of its proper divisors (6012070320).

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

1981450800 is a wasteful number, since it uses less digits than its factorization.

1981450800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381 (or 1367 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 1981450800 is about 44513.4900900839. The cubic root of 1981450800 is about 1256.0138577453.

The spelling of 1981450800 in words is "one billion, nine hundred eighty-one million, four hundred fifty thousand, eight hundred".