813604 has 27 divisors (see below), whose sum is σ = 1604113. Its totient is φ = 360800.

The previous prime is 813601. The next prime is 813613. The reversal of 813604 is 406318.

The square root of 813604 is 902.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 39204 + 774400 = 198^2 + 880^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a Duffinian number.

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 8 ways as a sum of consecutive naturals, for example, 19824 + ... + 19864.

2⁸¹³⁶⁰⁴ is an apocalyptic number.

813604 is the 902-nd square number.

It is an amenable number.

813604 is a deficient number, since it is larger than the sum of its proper divisors (790509).

813604 is a wasteful number, since it uses less digits than its factorization.

813604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The cubic root of 813604 is about 93.3550233037.

Multiplying 813604 by its product of nonzero digits (576), we get a square (468635904 = 21648²).

The spelling of 813604 in words is "eight hundred thirteen thousand, six hundred four".