28400303 has 4 divisors (see below), whose sum is σ = 28420080. Its totient is φ = 28380528.

The previous prime is 28400279. The next prime is 28400311. The reversal of 28400303 is 30300482.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28400303 - 2¹⁰ = 28399279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28400503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7550 + ... + 10667.

It is an arithmetic number, because the mean of its divisors is an integer number (7105020).

Almost surely, 2^28400303 is an apocalyptic number.

28400303 is a deficient number, since it is larger than the sum of its proper divisors (19777).

28400303 is a wasteful number, since it uses less digits than its factorization.

28400303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19776.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 28400303 is about 5329.1934661823. The cubic root of 28400303 is about 305.0991454080.

Adding to 28400303 its reverse (30300482), we get a palindrome (58700785).

The spelling of 28400303 in words is "twenty-eight million, four hundred thousand, three hundred three".