320820166400 has 108 divisors (see below), whose sum is σ = 804959020992. Its totient is φ = 126569963520.

The previous prime is 320820166397. The next prime is 320820166441. The reversal of 320820166400 is 4661028023.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 123857 + ... + 810543.

Almost surely, 2^320820166400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 320820166400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (402479510496).

320820166400 is an abundant number, since it is smaller than the sum of its proper divisors (484138854592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

320820166400 is an equidigital number, since it uses as much as digits as its factorization.

320820166400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686786 (or 686767 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 32.

The spelling of 320820166400 in words is "three hundred twenty billion, eight hundred twenty million, one hundred sixty-six thousand, four hundred".