991337 has 4 divisors (see below), whose sum is σ = 996996. Its totient is φ = 985680.

The previous prime is 991327. The next prime is 991343. The reversal of 991337 is 733199.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 733199 = 79 ⋅9281.

It can be written as a sum of positive squares in 2 ways, for example, as 534361 + 456976 = 731^2 + 676^2 .

It is a cyclic number.

It is not a de Polignac number, because 991337 - 2⁶ = 991273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991327) 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, 2558 + ... + 2919.

It is an arithmetic number, because the mean of its divisors is an integer number (249249).

2⁹⁹¹³³⁷ is an apocalyptic number.

It is an amenable number.

991337 is a deficient number, since it is larger than the sum of its proper divisors (5659).

991337 is a wasteful number, since it uses less digits than its factorization.

991337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5658.

The product of its digits is 5103, while the sum is 32.

The square root of 991337 is about 995.6590781990. The cubic root of 991337 is about 99.7103954349.

The spelling of 991337 in words is "nine hundred ninety-one thousand, three hundred thirty-seven".