1987983 has 20 divisors (see below), whose sum is σ = 3011448. Its totient is φ = 1312200.

The previous prime is 1987981. The next prime is 1987987. The reversal of 1987983 is 3897891.

It is not a de Polignac number, because 1987983 - 2¹ = 1987981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987981) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 19633 + ... + 19733.

2^1987983 is an apocalyptic number.

1987983 is a deficient number, since it is larger than the sum of its proper divisors (1023465).

1987983 is an frugal number, since it uses more digits than its factorization.

1987983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 104 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 1987983 is about 1409.9585100279. The cubic root of 1987983 is about 125.7392567107.

The spelling of 1987983 in words is "one million, nine hundred eighty-seven thousand, nine hundred eighty-three".