981589 has 4 divisors (see below), whose sum is σ = 1121824. Its totient is φ = 841356.

The previous prime is 981587. The next prime is 981599. The reversal of 981589 is 985189.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 985189 = 41 ⋅24029.

It is a cyclic number.

It is not a de Polignac number, because 981589 - 2¹ = 981587 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981587) 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 3 ways as a sum of consecutive naturals, for example, 70107 + ... + 70120.

It is an arithmetic number, because the mean of its divisors is an integer number (280456).

2⁹⁸¹⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

981589 is a deficient number, since it is larger than the sum of its proper divisors (140235).

981589 is a wasteful number, since it uses less digits than its factorization.

981589 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140234.

The product of its digits is 25920, while the sum is 40.

The square root of 981589 is about 990.7517347954. The cubic root of 981589 is about 99.3824947211.

Subtracting 981589 from its reverse (985189), we obtain a square (3600 = 60²).

The spelling of 981589 in words is "nine hundred eighty-one thousand, five hundred eighty-nine".