991436 has 12 divisors (see below), whose sum is σ = 1764840. Its totient is φ = 487200.

The previous prime is 991429. The next prime is 991447. The reversal of 991436 is 634199.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991436.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1865 + ... + 2336.

It is an arithmetic number, because the mean of its divisors is an integer number (147070).

2⁹⁹¹⁴³⁶ is an apocalyptic number.

It is an amenable number.

991436 is a deficient number, since it is larger than the sum of its proper divisors (773404).

991436 is a wasteful number, since it uses less digits than its factorization.

991436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4264 (or 4262 counting only the distinct ones).

The product of its digits is 5832, while the sum is 32.

The square root of 991436 is about 995.7087927703. The cubic root of 991436 is about 99.7137145217.

The spelling of 991436 in words is "nine hundred ninety-one thousand, four hundred thirty-six".