991038 has 8 divisors (see below), whose sum is σ = 1982088. Its totient is φ = 330344.

The previous prime is 991037. The next prime is 991043. The reversal of 991038 is 830199.

It is a happy number.

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

991038 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 990996 and 991014.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991038.

It is not an unprimeable number, because it can be changed into a prime (991031) 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, 82581 + ... + 82592.

It is an arithmetic number, because the mean of its divisors is an integer number (247761).

2⁹⁹¹⁰³⁸ is an apocalyptic number.

991038 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

991038 is a wasteful number, since it uses less digits than its factorization.

991038 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165178.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 991038 is about 995.5089150781. The cubic root of 991038 is about 99.7003697807.

The spelling of 991038 in words is "nine hundred ninety-one thousand, thirty-eight".