816947873280 has 2560 divisors, whose sum is σ = 3846610944000. Its totient is φ = 159411732480.

The previous prime is 816947873249. The next prime is 816947873281. The reversal of 816947873280 is 82378749618.

816947873280 is a `hidden beast` number, since 8 + 16 + 9 + 478 + 73 + 2 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (2560).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816947873281) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 10341112281 + ... + 10341112359.

It is an arithmetic number, because the mean of its divisors is an integer number (1502582400).

Almost surely, 2^816947873280 is an apocalyptic number.

816947873280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 816947873280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1923305472000).

816947873280 is an abundant number, since it is smaller than the sum of its proper divisors (3029663070720).

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

816947873280 is a wasteful number, since it uses less digits than its factorization.

816947873280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 32514048, while the sum is 63.

The spelling of 816947873280 in words is "eight hundred sixteen billion, nine hundred forty-seven million, eight hundred seventy-three thousand, two hundred eighty".