28473121 has 4 divisors (see below), whose sum is σ = 28681092. Its totient is φ = 28265152.

The previous prime is 28473083. The next prime is 28473161. The reversal of 28473121 is 12137482.

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 16646400 + 11826721 = 4080^2 + 3439^2 .

It is a cyclic number.

It is not a de Polignac number, because 28473121 - 2¹⁵ = 28440353 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28473121.

It is not an unprimeable number, because it can be changed into a prime (28473161) 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, 103780 + ... + 104053.

It is an arithmetic number, because the mean of its divisors is an integer number (7170273).

Almost surely, 2^28473121 is an apocalyptic number.

It is an amenable number.

28473121 is a deficient number, since it is larger than the sum of its proper divisors (207971).

28473121 is a wasteful number, since it uses less digits than its factorization.

28473121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207970.

The product of its digits is 2688, while the sum is 28.

The square root of 28473121 is about 5336.0210831667. The cubic root of 28473121 is about 305.3596795860.

The spelling of 28473121 in words is "twenty-eight million, four hundred seventy-three thousand, one hundred twenty-one".