813973 has 4 divisors (see below), whose sum is σ = 833868. Its totient is φ = 794080.

The previous prime is 813971. The next prime is 813991. The reversal of 813973 is 379318.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 79524 + 734449 = 282^2 + 857^2 .

It is a cyclic number.

It is not a de Polignac number, because 813973 - 2¹ = 813971 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

813973 is a lucky number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9886 + ... + 9967.

It is an arithmetic number, because the mean of its divisors is an integer number (208467).

2⁸¹³⁹⁷³ is an apocalyptic number.

It is an amenable number.

813973 is a deficient number, since it is larger than the sum of its proper divisors (19895).

813973 is a wasteful number, since it uses less digits than its factorization.

813973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19894.

The product of its digits is 4536, while the sum is 31.

The square root of 813973 is about 902.2045222675. The cubic root of 813973 is about 93.3691345081.

The spelling of 813973 in words is "eight hundred thirteen thousand, nine hundred seventy-three".