28309273 has 2 divisors, whose sum is σ = 28309274. Its totient is φ = 28309272.

The previous prime is 28309271. The next prime is 28309277. The reversal of 28309273 is 37290382.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25080064 + 3229209 = 5008^2 + 1797^2 .

It is a cyclic number.

It is not a de Polignac number, because 28309273 - 2¹ = 28309271 is a prime.

Together with 28309271, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28309271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14154636 + 14154637.

It is an arithmetic number, because the mean of its divisors is an integer number (14154637).

Almost surely, 2^28309273 is an apocalyptic number.

It is an amenable number.

28309273 is a deficient number, since it is larger than the sum of its proper divisors (1).

28309273 is an equidigital number, since it uses as much as digits as its factorization.

28309273 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 28309273 is about 5320.6459194350. The cubic root of 28309273 is about 304.7728237551.

It can be divided in two parts, 28309 and 273, that added together give a palindrome (28582).

The spelling of 28309273 in words is "twenty-eight million, three hundred nine thousand, two hundred seventy-three".