981591 has 8 divisors (see below), whose sum is σ = 1409520. Its totient is φ = 604032.

The previous prime is 981587. The next prime is 981599. The reversal of 981591 is 195189.

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

It is not a de Polignac number, because 981591 - 2² = 981587 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981599) 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, 12546 + ... + 12623.

It is an arithmetic number, because the mean of its divisors is an integer number (176190).

2⁹⁸¹⁵⁹¹ is an apocalyptic number.

981591 is a deficient number, since it is larger than the sum of its proper divisors (427929).

981591 is a wasteful number, since it uses less digits than its factorization.

981591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25185.

The product of its digits is 3240, while the sum is 33.

The square root of 981591 is about 990.7527441294. The cubic root of 981591 is about 99.3825622187.

The spelling of 981591 in words is "nine hundred eighty-one thousand, five hundred ninety-one".