28400211 has 12 divisors (see below), whose sum is σ = 46882992. Its totient is φ = 16228656.

The previous prime is 28400159. The next prime is 28400219. The reversal of 28400211 is 11200482.

It is not a de Polignac number, because 28400211 - 2¹⁹ = 27875923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28400219) by changing a digit.

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, 225336 + ... + 225461.

It is an arithmetic number, because the mean of its divisors is an integer number (3906916).

Almost surely, 2^28400211 is an apocalyptic number.

28400211 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28400211 is a deficient number, since it is larger than the sum of its proper divisors (18482781).

28400211 is a wasteful number, since it uses less digits than its factorization.

28400211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450810 (or 450807 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 28400211 is about 5329.1848344752. The cubic root of 28400211 is about 305.0988159614.

Adding to 28400211 its reverse (11200482), we get a palindrome (39600693).

The spelling of 28400211 in words is "twenty-eight million, four hundred thousand, two hundred eleven".