813623 has 2 divisors, whose sum is σ = 813624. Its totient is φ = 813622.

The previous prime is 813613. The next prime is 813647. The reversal of 813623 is 326318.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 813623 - 2⁶ = 813559 is a prime.

It is a super-2 number, since 2×813623² = 1323964772258, which contains 22 as substring.

It is a Sophie Germain prime.

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 (813613) 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, 406811 + 406812.

It is an arithmetic number, because the mean of its divisors is an integer number (406812).

2⁸¹³⁶²³ is an apocalyptic number.

813623 is a deficient number, since it is larger than the sum of its proper divisors (1).

813623 is an equidigital number, since it uses as much as digits as its factorization.

813623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

The square root of 813623 is about 902.0105320893. The cubic root of 813623 is about 93.3557500011.

It can be divided in two parts, 8 and 13623, that added together give a palindrome (13631).

The spelling of 813623 in words is "eight hundred thirteen thousand, six hundred twenty-three".