28081801188 has 144 divisors (see below), whose sum is σ = 85346352000. Its totient is φ = 7615286784.

The previous prime is 28081801103. The next prime is 28081801193. The reversal of 28081801188 is 88110818082.

It is a super-2 number, since 2×28081801188² (a number of 22 digits) contains 22 as substring.

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, 398608 + ... + 463736.

It is an arithmetic number, because the mean of its divisors is an integer number (592683000).

Almost surely, 2^28081801188 is an apocalyptic number.

28081801188 is a gapful number since it is divisible by the number (28) 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 28081801188, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42673176000).

28081801188 is an abundant number, since it is smaller than the sum of its proper divisors (57264550812).

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

28081801188 is a wasteful number, since it uses less digits than its factorization.

28081801188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65234 (or 65229 counting only the distinct ones).

The product of its (nonzero) digits is 65536, while the sum is 45.

The spelling of 28081801188 in words is "twenty-eight billion, eighty-one million, eight hundred one thousand, one hundred eighty-eight".