831305213 has 4 divisors (see below), whose sum is σ = 859970940. Its totient is φ = 802639488.

The previous prime is 831305203. The next prime is 831305227. The reversal of 831305213 is 312503138.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312503138 = 2 ⋅156251569.

It can be written as a sum of positive squares in 2 ways, for example, as 413634244 + 417670969 = 20338^2 + 20437^2 .

It is a cyclic number.

It is not a de Polignac number, because 831305213 - 2¹⁰ = 831304189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (831305203) 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, 14332820 + ... + 14332877.

It is an arithmetic number, because the mean of its divisors is an integer number (214992735).

Almost surely, 2^831305213 is an apocalyptic number.

It is an amenable number.

831305213 is a deficient number, since it is larger than the sum of its proper divisors (28665727).

831305213 is a wasteful number, since it uses less digits than its factorization.

831305213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28665726.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 831305213 is about 28832.3639856325. The cubic root of 831305213 is about 940.2719950025.

The spelling of 831305213 in words is "eight hundred thirty-one million, three hundred five thousand, two hundred thirteen".