19981312 has 88 divisors (see below), whose sum is σ = 45852800. Its totient is φ = 8626176.

The previous prime is 19981303. The next prime is 19981333. The reversal of 19981312 is 21318991.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252889 + ... + 252967.

Almost surely, 2^19981312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19981312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22926400).

19981312 is an abundant number, since it is smaller than the sum of its proper divisors (25871488).

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

19981312 is a wasteful number, since it uses less digits than its factorization.

19981312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 113 counting only the distinct ones).

The product of its digits is 3888, while the sum is 34.

The square root of 19981312 is about 4470.0460847736. The cubic root of 19981312 is about 271.3571902521.

The spelling of 19981312 in words is "nineteen million, nine hundred eighty-one thousand, three hundred twelve".