809605220164 has 96 divisors (see below), whose sum is σ = 1577548967904. Its totient is φ = 361236049920.

The previous prime is 809605220089. The next prime is 809605220167. The reversal of 809605220164 is 461022506908.

It can be written as a sum of positive squares in 16 ways, for example, as 117367908100 + 692237312064 = 342590^2 + 832008^2 .

It is a super-2 number, since 2×809605220164² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 809605220164.

It is not an unprimeable number, because it can be changed into a prime (809605220167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 67839942 + ... + 67851874.

It is an arithmetic number, because the mean of its divisors is an integer number (16432801749).

Almost surely, 2^809605220164 is an apocalyptic number.

It is an amenable number.

809605220164 is a deficient number, since it is larger than the sum of its proper divisors (767943747740).

809605220164 is a wasteful number, since it uses less digits than its factorization.

809605220164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12377 (or 12375 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 43.

The spelling of 809605220164 in words is "eight hundred nine billion, six hundred five million, two hundred twenty thousand, one hundred sixty-four".