1988815 has 4 divisors (see below), whose sum is σ = 2386584. Its totient is φ = 1591048.

The previous prime is 1988807. The next prime is 1988837. The reversal of 1988815 is 5188891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5188891 = 1399 ⋅3709.

It is a cyclic number.

It is not a de Polignac number, because 1988815 - 2³ = 1988807 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 198877 + ... + 198886.

It is an arithmetic number, because the mean of its divisors is an integer number (596646).

2^1988815 is an apocalyptic number.

1988815 is a deficient number, since it is larger than the sum of its proper divisors (397769).

1988815 is an equidigital number, since it uses as much as digits as its factorization.

1988815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397768.

The product of its digits is 23040, while the sum is 40.

The square root of 1988815 is about 1410.2535233071. The cubic root of 1988815 is about 125.7567955043.

The spelling of 1988815 in words is "one million, nine hundred eighty-eight thousand, eight hundred fifteen".