28273181 has 2 divisors, whose sum is σ = 28273182. Its totient is φ = 28273180.

The previous prime is 28273177. The next prime is 28273207. The reversal of 28273181 is 18137282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19061956 + 9211225 = 4366^2 + 3035^2 .

It is a cyclic number.

It is not a de Polignac number, because 28273181 - 2² = 28273177 is a prime.

It is a super-2 number, since 2×28273181² = 1598745527717522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28273111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14136590 + 14136591.

It is an arithmetic number, because the mean of its divisors is an integer number (14136591).

Almost surely, 2^28273181 is an apocalyptic number.

It is an amenable number.

28273181 is a deficient number, since it is larger than the sum of its proper divisors (1).

28273181 is an equidigital number, since it uses as much as digits as its factorization.

28273181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 32.

The square root of 28273181 is about 5317.2531442466. The cubic root of 28273181 is about 304.6432485601.

The spelling of 28273181 in words is "twenty-eight million, two hundred seventy-three thousand, one hundred eighty-one".