823638913 has 2 divisors, whose sum is σ = 823638914. Its totient is φ = 823638912.

The previous prime is 823638863. The next prime is 823638917. The reversal of 823638913 is 319836328.

823638913 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 823517809 + 121104 = 28697^2 + 348^2 .

It is a cyclic number.

It is not a de Polignac number, because 823638913 - 2²⁵ = 790084481 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 823638913.

It is not a weakly prime, because it can be changed into another prime (823638917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 411819456 + 411819457.

It is an arithmetic number, because the mean of its divisors is an integer number (411819457).

Almost surely, 2^823638913 is an apocalyptic number.

It is an amenable number.

823638913 is a deficient number, since it is larger than the sum of its proper divisors (1).

823638913 is an equidigital number, since it uses as much as digits as its factorization.

823638913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 43.

The square root of 823638913 is about 28699.1099687778. The cubic root of 823638913 is about 937.3726667476.

The spelling of 823638913 in words is "eight hundred twenty-three million, six hundred thirty-eight thousand, nine hundred thirteen".