1988785 has 4 divisors (see below), whose sum is σ = 2386548. Its totient is φ = 1591024.

The previous prime is 1988759. The next prime is 1988797. The reversal of 1988785 is 5878891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5878891 = 331 ⋅17761.

It can be written as a sum of positive squares in 2 ways, for example, as 1468944 + 519841 = 1212^2 + 721^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1988785 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198874 + ... + 198883.

It is an arithmetic number, because the mean of its divisors is an integer number (596637).

2^1988785 is an apocalyptic number.

It is an amenable number.

1988785 is a deficient number, since it is larger than the sum of its proper divisors (397763).

1988785 is an equidigital number, since it uses as much as digits as its factorization.

1988785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397762.

The product of its digits is 161280, while the sum is 46.

The square root of 1988785 is about 1410.2428868815. The cubic root of 1988785 is about 125.7561631809.

It can be divided in two parts, 19 and 88785, that added together give a square (88804 = 298²).

The spelling of 1988785 in words is "one million, nine hundred eighty-eight thousand, seven hundred eighty-five".