973991 has 4 divisors (see below), whose sum is σ = 986400. Its totient is φ = 961584.

The previous prime is 973957. The next prime is 974003. The reversal of 973991 is 199379.

It is a happy number.

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 973991 - 2¹⁰ = 972967 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (973901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6086 + ... + 6243.

It is an arithmetic number, because the mean of its divisors is an integer number (246600).

2⁹⁷³⁹⁹¹ is an apocalyptic number.

973991 is a deficient number, since it is larger than the sum of its proper divisors (12409).

973991 is a wasteful number, since it uses less digits than its factorization.

973991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12408.

The product of its digits is 15309, while the sum is 38.

The square root of 973991 is about 986.9098236415. The cubic root of 973991 is about 99.1254064950.

The spelling of 973991 in words is "nine hundred seventy-three thousand, nine hundred ninety-one".