28080065680 has 80 divisors (see below), whose sum is σ = 66835347264. Its totient is φ = 10967523840.

The previous prime is 28080065659. The next prime is 28080065687. The reversal of 28080065680 is 8656008082.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×28080065680² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28080065687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 878947 + ... + 910333.

Almost surely, 2^28080065680 is an apocalyptic number.

28080065680 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 28080065680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33417673632).

28080065680 is an abundant number, since it is smaller than the sum of its proper divisors (38755281584).

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

28080065680 is a wasteful number, since it uses less digits than its factorization.

28080065680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31664 (or 31658 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 43.

The spelling of 28080065680 in words is "twenty-eight billion, eighty million, sixty-five thousand, six hundred eighty".