813817 has 2 divisors, whose sum is σ = 813818. Its totient is φ = 813816.

The previous prime is 813811. The next prime is 813829. The reversal of 813817 is 718318.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 698896 + 114921 = 836^2 + 339^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-813817 is a prime.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (813811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406908 + 406909.

It is an arithmetic number, because the mean of its divisors is an integer number (406909).

2⁸¹³⁸¹⁷ is an apocalyptic number.

It is an amenable number.

813817 is a deficient number, since it is larger than the sum of its proper divisors (1).

813817 is an equidigital number, since it uses as much as digits as its factorization.

813817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1344, while the sum is 28.

The square root of 813817 is about 902.1180632268. The cubic root of 813817 is about 93.3631693162.

The spelling of 813817 in words is "eight hundred thirteen thousand, eight hundred seventeen".