991339 has 4 divisors (see below), whose sum is σ = 1015560. Its totient is φ = 967120.

The previous prime is 991327. The next prime is 991343. The reversal of 991339 is 933199.

It is a happy number.

991339 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 991339 - 2¹⁷ = 860267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (994339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12049 + ... + 12130.

It is an arithmetic number, because the mean of its divisors is an integer number (253890).

2⁹⁹¹³³⁹ is an apocalyptic number.

991339 is a deficient number, since it is larger than the sum of its proper divisors (24221).

991339 is a wasteful number, since it uses less digits than its factorization.

991339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24220.

The product of its digits is 6561, while the sum is 34.

The square root of 991339 is about 995.6600825583. The cubic root of 991339 is about 99.7104624894.

The spelling of 991339 in words is "nine hundred ninety-one thousand, three hundred thirty-nine".