8321813 has 2 divisors, whose sum is σ = 8321814. Its totient is φ = 8321812.

The previous prime is 8321809. The next prime is 8321843. The reversal of 8321813 is 3181238.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7941124 + 380689 = 2818^2 + 617^2 .

It is a cyclic number.

It is not a de Polignac number, because 8321813 - 2² = 8321809 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8321843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4160906 + 4160907.

It is an arithmetic number, because the mean of its divisors is an integer number (4160907).

Almost surely, 2^8321813 is an apocalyptic number.

It is an amenable number.

8321813 is a deficient number, since it is larger than the sum of its proper divisors (1).

8321813 is an equidigital number, since it uses as much as digits as its factorization.

8321813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 26.

The square root of 8321813 is about 2884.7552755823. The cubic root of 8321813 is about 202.6465981085.

The spelling of 8321813 in words is "eight million, three hundred twenty-one thousand, eight hundred thirteen".