1988791 has 16 divisors (see below), whose sum is σ = 2399040. Its totient is φ = 1612800.

The previous prime is 1988759. The next prime is 1988797. The reversal of 1988791 is 1978891.

It is not a de Polignac number, because 1988791 - 2⁵ = 1988759 is a prime.

It is a super-3 number, since 3×1988791³ = 23598733325305193013, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1988797) 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 15 ways as a sum of consecutive naturals, for example, 19641 + ... + 19741.

It is an arithmetic number, because the mean of its divisors is an integer number (149940).

2^1988791 is an apocalyptic number.

1988791 is a deficient number, since it is larger than the sum of its proper divisors (410249).

1988791 is a wasteful number, since it uses less digits than its factorization.

1988791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234.

The product of its digits is 36288, while the sum is 43.

The square root of 1988791 is about 1410.2450141731. The cubic root of 1988791 is about 125.7562896461.

The spelling of 1988791 in words is "one million, nine hundred eighty-eight thousand, seven hundred ninety-one".