28299121 has 4 divisors (see below), whose sum is σ = 28339200. Its totient is φ = 28259044.

The previous prime is 28299091. The next prime is 28299127. The reversal of 28299121 is 12199282.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12199282 = 2 ⋅6099641.

It is a cyclic number.

It is not a de Polignac number, because 28299121 - 2⁹ = 28298609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28299127) 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 in 3 ways as a sum of consecutive naturals, for example, 18961 + ... + 20398.

It is an arithmetic number, because the mean of its divisors is an integer number (7084800).

Almost surely, 2^28299121 is an apocalyptic number.

It is an amenable number.

28299121 is a deficient number, since it is larger than the sum of its proper divisors (40079).

28299121 is an equidigital number, since it uses as much as digits as its factorization.

28299121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40078.

The product of its digits is 5184, while the sum is 34.

The square root of 28299121 is about 5319.6918143817. The cubic root of 28299121 is about 304.7363878302.

The spelling of 28299121 in words is "twenty-eight million, two hundred ninety-nine thousand, one hundred twenty-one".