28207528181 has 16 divisors (see below), whose sum is σ = 32329188864. Its totient is φ = 24108948864.

The previous prime is 28207528121. The next prime is 28207528229. The reversal of 28207528181 is 18182570282.

It is a happy number.

It is not a de Polignac number, because 28207528181 - 2²⁶ = 28140419317 is a prime.

It is a super-2 number, since 2×28207528181² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28207528121) 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, 7753895 + ... + 7757531.

It is an arithmetic number, because the mean of its divisors is an integer number (2020574304).

Almost surely, 2^28207528181 is an apocalyptic number.

It is an amenable number.

28207528181 is a deficient number, since it is larger than the sum of its proper divisors (4121660683).

28207528181 is a wasteful number, since it uses less digits than its factorization.

28207528181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6500.

The product of its (nonzero) digits is 143360, while the sum is 44.

The spelling of 28207528181 in words is "twenty-eight billion, two hundred seven million, five hundred twenty-eight thousand, one hundred eighty-one".