28144921878864 has 400 divisors, whose sum is σ = 93594920791680. Its totient is φ = 7998455808000.

The previous prime is 28144921878847. The next prime is 28144921878907. The reversal of 28144921878864 is 46887812944182.

28144921878864 is a `hidden beast` number, since 2 + 8 + 1 + 4 + 492 + 1 + 8 + 78 + 8 + 64 = 666.

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

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 28144921878792 and 28144921878801.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1751060332 + ... + 1751076404.

Almost surely, 2^{28144921878864} is an apocalyptic number.

28144921878864 is a gapful number since it is divisible by the number (24) 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 28144921878864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46797460395840).

28144921878864 is an abundant number, since it is smaller than the sum of its proper divisors (65449998912816).

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

28144921878864 is a wasteful number, since it uses less digits than its factorization.

28144921878864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17120 (or 17105 counting only the distinct ones).

The product of its digits is 396361728, while the sum is 72.

The spelling of 28144921878864 in words is "twenty-eight trillion, one hundred forty-four billion, nine hundred twenty-one million, eight hundred seventy-eight thousand, eight hundred sixty-four".