813863 has 2 divisors, whose sum is σ = 813864. Its totient is φ = 813862.

The previous prime is 813847. The next prime is 813871. The reversal of 813863 is 368318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 813863 - 2⁴ = 813847 is a prime.

It is a Sophie Germain prime.

It is an Ulam number.

It is a plaindrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (813833) 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 as a sum of consecutive naturals, namely, 406931 + 406932.

It is an arithmetic number, because the mean of its divisors is an integer number (406932).

2⁸¹³⁸⁶³ is an apocalyptic number.

813863 is a deficient number, since it is larger than the sum of its proper divisors (1).

813863 is an equidigital number, since it uses as much as digits as its factorization.

813863 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 29.

The square root of 813863 is about 902.1435584207. The cubic root of 813863 is about 93.3649283623.

The spelling of 813863 in words is "eight hundred thirteen thousand, eight hundred sixty-three".