1989591 has 8 divisors (see below), whose sum is σ = 2676720. Its totient is φ = 1314432.

The previous prime is 1989583. The next prime is 1989613. The reversal of 1989591 is 1959891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1989591 - 2³ = 1989583 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2596 + ... + 3273.

It is an arithmetic number, because the mean of its divisors is an integer number (334590).

2^1989591 is an apocalyptic number.

1989591 is a deficient number, since it is larger than the sum of its proper divisors (687129).

1989591 is a wasteful number, since it uses less digits than its factorization.

1989591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5985.

The product of its digits is 29160, while the sum is 42.

The square root of 1989591 is about 1410.5286243108. The cubic root of 1989591 is about 125.7731493941.

The spelling of 1989591 in words is "one million, nine hundred eighty-nine thousand, five hundred ninety-one".