28211345 has 12 divisors (see below), whose sum is σ = 35066460. Its totient is φ = 21787584.

The previous prime is 28211303. The next prime is 28211377. The reversal of 28211345 is 54311282.

It can be written as a sum of positive squares in 6 ways, for example, as 36481 + 28174864 = 191^2 + 5308^2 .

It is not a de Polignac number, because 28211345 - 2¹⁰ = 28210321 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 851 + ... + 7559.

It is an arithmetic number, because the mean of its divisors is an integer number (2922205).

Almost surely, 2^28211345 is an apocalyptic number.

It is an amenable number.

28211345 is a deficient number, since it is larger than the sum of its proper divisors (6855115).

28211345 is an equidigital number, since it uses as much as digits as its factorization.

28211345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6772 (or 6743 counting only the distinct ones).

The product of its digits is 1920, while the sum is 26.

The square root of 28211345 is about 5311.4353050753. The cubic root of 28211345 is about 304.4209923515.

The spelling of 28211345 in words is "twenty-eight million, two hundred eleven thousand, three hundred forty-five".