28512229 has 2 divisors, whose sum is σ = 28512230. Its totient is φ = 28512228.

The previous prime is 28512173. The next prime is 28512257. The reversal of 28512229 is 92221582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16016004 + 12496225 = 4002^2 + 3535^2 .

It is a cyclic number.

It is not a de Polignac number, because 28512229 - 2⁷ = 28512101 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28512229.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28512259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14256114 + 14256115.

It is an arithmetic number, because the mean of its divisors is an integer number (14256115).

Almost surely, 2^28512229 is an apocalyptic number.

It is an amenable number.

28512229 is a deficient number, since it is larger than the sum of its proper divisors (1).

28512229 is an equidigital number, since it uses as much as digits as its factorization.

28512229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 31.

The square root of 28512229 is about 5339.6843539670. The cubic root of 28512229 is about 305.4994200690.

The spelling of 28512229 in words is "twenty-eight million, five hundred twelve thousand, two hundred twenty-nine".