28227181 has 2 divisors, whose sum is σ = 28227182. Its totient is φ = 28227180.

The previous prime is 28227169. The next prime is 28227197. The reversal of 28227181 is 18172282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20331081 + 7896100 = 4509^2 + 2810^2 .

It is a cyclic number.

It is not a de Polignac number, because 28227181 - 2⁵ = 28227149 is a prime.

It is a super-4 number, since 4×28227181⁴ (a number of 31 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a nialpdrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28227281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14113590 + 14113591.

It is an arithmetic number, because the mean of its divisors is an integer number (14113591).

Almost surely, 2^28227181 is an apocalyptic number.

It is an amenable number.

28227181 is a deficient number, since it is larger than the sum of its proper divisors (1).

28227181 is an equidigital number, since it uses as much as digits as its factorization.

28227181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3584, while the sum is 31.

The square root of 28227181 is about 5312.9258417561. The cubic root of 28227181 is about 304.4779423609.

The spelling of 28227181 in words is "twenty-eight million, two hundred twenty-seven thousand, one hundred eighty-one".