28856720551680 has 3240 divisors, whose sum is σ = 128250869281920. Its totient is φ = 6170237337600.

The previous prime is 28856720551661. The next prime is 28856720551709. The reversal of 28856720551680 is 8615502765882.

It is a happy number.

28856720551680 is a `hidden beast` number, since 2 + 8 + 8 + 5 + 6 + 72 + 0 + 551 + 6 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (3240).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 264740555466 + ... + 264740555574.

Almost surely, 2^{28856720551680} is an apocalyptic number.

28856720551680 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 28856720551680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64125434640960).

28856720551680 is an abundant number, since it is smaller than the sum of its proper divisors (99394148730240).

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

28856720551680 is a wasteful number, since it uses less digits than its factorization.

28856720551680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 198 counting only the distinct ones).

The product of its (nonzero) digits is 64512000, while the sum is 63.

The spelling of 28856720551680 in words is "twenty-eight trillion, eight hundred fifty-six billion, seven hundred twenty million, five hundred fifty-one thousand, six hundred eighty".