813603 has 32 divisors (see below), whose sum is σ = 1368576. Its totient is φ = 419328.

The previous prime is 813601. The next prime is 813613. The reversal of 813603 is 306318.

It is a Cunningham number, because it is equal to 902²-1.

It is not a de Polignac number, because 813603 - 2¹ = 813601 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 813603.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 813603.

It is not an unprimeable number, because it can be changed into a prime (813601) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15325 + ... + 15377.

It is an arithmetic number, because the mean of its divisors is an integer number (42768).

2⁸¹³⁶⁰³ is an apocalyptic number.

813603 is a deficient number, since it is larger than the sum of its proper divisors (554973).

813603 is a wasteful number, since it uses less digits than its factorization.

813603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 813603 is about 901.9994456761. Note that the first 3 decimals coincide. The cubic root of 813603 is about 93.3549850562.

The spelling of 813603 in words is "eight hundred thirteen thousand, six hundred three".