28225181 has 2 divisors, whose sum is σ = 28225182. Its totient is φ = 28225180.

The previous prime is 28225177. The next prime is 28225189. The reversal of 28225181 is 18152282.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27984100 + 241081 = 5290^2 + 491^2 .

It is a cyclic number.

It is not a de Polignac number, because 28225181 - 2² = 28225177 is a prime.

It is a super-2 number, since 2×28225181² = 1593321684965522, which contains 22 as substring.

It is equal to p_1754552 and since 28225181 and 1754552 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28225189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14112590 + 14112591.

It is an arithmetic number, because the mean of its divisors is an integer number (14112591).

Almost surely, 2^28225181 is an apocalyptic number.

It is an amenable number.

28225181 is a deficient number, since it is larger than the sum of its proper divisors (1).

28225181 is an equidigital number, since it uses as much as digits as its factorization.

28225181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2560, while the sum is 29.

The square root of 28225181 is about 5312.7376182153. The cubic root of 28225181 is about 304.4707510622.

The spelling of 28225181 in words is "twenty-eight million, two hundred twenty-five thousand, one hundred eighty-one".