1981116 has 36 divisors (see below), whose sum is σ = 5062512. Its totient is φ = 653184.

The previous prime is 1981099. The next prime is 1981141. The reversal of 1981116 is 6111891.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1981116.

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 11 ways as a sum of consecutive naturals, for example, 3825 + ... + 4311.

2^1981116 is an apocalyptic number.

It is an amenable number.

1981116 is an abundant number, since it is smaller than the sum of its proper divisors (3081396).

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

1981116 is a wasteful number, since it uses less digits than its factorization.

1981116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610 (or 605 counting only the distinct ones).

The product of its digits is 432, while the sum is 27.

The square root of 1981116 is about 1407.5212254172. The cubic root of 1981116 is about 125.5943112087.

The spelling of 1981116 in words is "one million, nine hundred eighty-one thousand, one hundred sixteen".