28480121 has 4 divisors (see below), whose sum is σ = 29249892. Its totient is φ = 27710352.

The previous prime is 28480099. The next prime is 28480129. The reversal of 28480121 is 12108482.

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

It can be written as a sum of positive squares in 2 ways, for example, as 25200400 + 3279721 = 5020^2 + 1811^2 .

It is a cyclic number.

It is not a de Polignac number, because 28480121 - 2⁶ = 28480057 is a prime.

It is a super-2 number, since 2×28480121² = 1622234584349282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28480129) 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 3 ways as a sum of consecutive naturals, for example, 384830 + ... + 384903.

It is an arithmetic number, because the mean of its divisors is an integer number (7312473).

Almost surely, 2^28480121 is an apocalyptic number.

It is an amenable number.

28480121 is a deficient number, since it is larger than the sum of its proper divisors (769771).

28480121 is an equidigital number, since it uses as much as digits as its factorization.

28480121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 769770.

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 28480121 is about 5336.6769623053. The cubic root of 28480121 is about 305.3847013438.

The spelling of 28480121 in words is "twenty-eight million, four hundred eighty thousand, one hundred twenty-one".