820556303 has 24 divisors (see below), whose sum is σ = 1010984832. Its totient is φ = 662652144.

The previous prime is 820556183. The next prime is 820556309. The reversal of 820556303 is 303655028.

It is not a de Polignac number, because 820556303 - 2¹⁶ = 820490767 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 820556303.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820556309) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70076 + ... + 80942.

It is an arithmetic number, because the mean of its divisors is an integer number (42124368).

Almost surely, 2^820556303 is an apocalyptic number.

820556303 is a deficient number, since it is larger than the sum of its proper divisors (190428529).

820556303 is a wasteful number, since it uses less digits than its factorization.

820556303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10971 (or 10964 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 820556303 is about 28645.3539513828. The cubic root of 820556303 is about 936.2017787491.

The spelling of 820556303 in words is "eight hundred twenty million, five hundred fifty-six thousand, three hundred three".