28549121 has 4 divisors (see below), whose sum is σ = 28560432. Its totient is φ = 28537812.

The previous prime is 28549093. The next prime is 28549123. The reversal of 28549121 is 12194582.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28549121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28549123) 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, 50 + ... + 7556.

It is an arithmetic number, because the mean of its divisors is an integer number (7140108).

It is a Proth number, since it is equal to 3485 ⋅ 2¹³ + 1 and 3485 < 2¹³.

Almost surely, 2^28549121 is an apocalyptic number.

It is an amenable number.

28549121 is a deficient number, since it is larger than the sum of its proper divisors (11311).

28549121 is an equidigital number, since it uses as much as digits as its factorization.

28549121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11310.

The product of its digits is 5760, while the sum is 32.

The square root of 28549121 is about 5343.1377485519. The cubic root of 28549121 is about 305.6311252768.

The spelling of 28549121 in words is "twenty-eight million, five hundred forty-nine thousand, one hundred twenty-one".