1981533384 has 48 divisors (see below), whose sum is σ = 5368708800. Its totient is φ = 660258144.

The previous prime is 1981533383. The next prime is 1981533397. The reversal of 1981533384 is 4833351891.

1981533384 is a `hidden beast` number, since 1 + 9 + 81 + 533 + 38 + 4 = 666.

It is not an unprimeable number, because it can be changed into a prime (1981533383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 339757 + ... + 345539.

It is an arithmetic number, because the mean of its divisors is an integer number (111848100).

Almost surely, 2^1981533384 is an apocalyptic number.

It is an amenable number.

1981533384 is an abundant number, since it is smaller than the sum of its proper divisors (3387175416).

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

1981533384 is a wasteful number, since it uses less digits than its factorization.

1981533384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10554 (or 10547 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 1981533384 is about 44514.4177093220. The cubic root of 1981533384 is about 1256.0313071158.

The spelling of 1981533384 in words is "one billion, nine hundred eighty-one million, five hundred thirty-three thousand, three hundred eighty-four".