28718784987840 has 336 divisors, whose sum is σ = 104149381845600. Its totient is φ = 7243427856384.

The previous prime is 28718784987833. The next prime is 28718784987877. The reversal of 28718784987840 is 4878948781782.

28718784987840 is a `hidden beast` number, since 2 + 8 + 7 + 1 + 87 + 8 + 498 + 7 + 8 + 40 = 666.

It is a super-2 number, since 2×28718784987840² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28718784987840.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 33115276 + ... + 33971444.

It is an arithmetic number, because the mean of its divisors is an integer number (309968398350).

Almost surely, 2^{28718784987840} is an apocalyptic number.

28718784987840 is a gapful number since it is divisible by the number (20) 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 28718784987840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52074690922800).

28718784987840 is an abundant number, since it is smaller than the sum of its proper divisors (75430596857760).

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

28718784987840 is a wasteful number, since it uses less digits than its factorization.

28718784987840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 856824 (or 856811 counting only the distinct ones).

The product of its (nonzero) digits is 3236954112, while the sum is 81.

The spelling of 28718784987840 in words is "twenty-eight trillion, seven hundred eighteen billion, seven hundred eighty-four million, nine hundred eighty-seven thousand, eight hundred forty".