28477121 has 4 divisors (see below), whose sum is σ = 28488132. Its totient is φ = 28466112.

The previous prime is 28477093. The next prime is 28477123. The reversal of 28477121 is 12177482.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 270400 + 28206721 = 520^2 + 5311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28477121 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 (28477123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 725 + ... + 7581.

It is an arithmetic number, because the mean of its divisors is an integer number (7122033).

Almost surely, 2^28477121 is an apocalyptic number.

It is an amenable number.

28477121 is a deficient number, since it is larger than the sum of its proper divisors (11011).

28477121 is an equidigital number, since it uses as much as digits as its factorization.

28477121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11010.

The product of its digits is 6272, while the sum is 32.

The square root of 28477121 is about 5336.3958811168. The cubic root of 28477121 is about 305.3739782354.

The spelling of 28477121 in words is "twenty-eight million, four hundred seventy-seven thousand, one hundred twenty-one".