816404163440 has 80 divisors (see below), whose sum is σ = 2020899404160. Its totient is φ = 305653985280.

The previous prime is 816404163383. The next prime is 816404163469. The reversal of 816404163440 is 44361404618.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1412120 + ... + 1904439.

It is an arithmetic number, because the mean of its divisors is an integer number (25261242552).

Almost surely, 2^816404163440 is an apocalyptic number.

816404163440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

816404163440 is an abundant number, since it is smaller than the sum of its proper divisors (1204495240720).

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

816404163440 is a wasteful number, since it uses less digits than its factorization.

816404163440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3316770 (or 3316764 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 41.

The spelling of 816404163440 in words is "eight hundred sixteen billion, four hundred four million, one hundred sixty-three thousand, four hundred forty".