28319955671808 has 216 divisors, whose sum is σ = 84714685526016. Its totient is φ = 9435852518400.

The previous prime is 28319955671803. The next prime is 28319955671857. The reversal of 28319955671808 is 80817655991382.

28319955671808 is a `hidden beast` number, since 28 + 31 + 9 + 9 + 5 + 567 + 1 + 8 + 0 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (216).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (28319955671801) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 143664193 + ... + 143861183.

It is an arithmetic number, because the mean of its divisors is an integer number (392197618176).

Almost surely, 2^{28319955671808} 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 28319955671808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42357342763008).

28319955671808 is an abundant number, since it is smaller than the sum of its proper divisors (56394729854208).

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

28319955671808 is an equidigital number, since it uses as much as digits as its factorization.

28319955671808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199333 (or 199307 counting only the distinct ones).

The product of its (nonzero) digits is 261273600, while the sum is 72.

The spelling of 28319955671808 in words is "twenty-eight trillion, three hundred nineteen billion, nine hundred fifty-five million, six hundred seventy-one thousand, eight hundred eight".