991340 has 48 divisors (see below), whose sum is σ = 2436672. Its totient is φ = 331776.

The previous prime is 991327. The next prime is 991343. The reversal of 991340 is 43199.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (991343) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10172 + ... + 10268.

It is an arithmetic number, because the mean of its divisors is an integer number (50764).

2⁹⁹¹³⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1218336).

991340 is an abundant number, since it is smaller than the sum of its proper divisors (1445332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

991340 is a wasteful number, since it uses less digits than its factorization.

991340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 991340 is about 995.6605847376. The cubic root of 991340 is about 99.7104960166.

It can be divided in two parts, 991 and 340, that added together give a palindrome (1331).

The spelling of 991340 in words is "nine hundred ninety-one thousand, three hundred forty".