28042481 has 4 divisors (see below), whose sum is σ = 28054500. Its totient is φ = 28030464.

The previous prime is 28042457. The next prime is 28042501. The reversal of 28042481 is 18424082.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18424082 = 2 ⋅9212041.

It can be written as a sum of positive squares in 2 ways, for example, as 8761600 + 19280881 = 2960^2 + 4391^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28042481 is a prime.

It is a super-2 number, since 2×28042481² = 1572761481270722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28042181) 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, 1256 + ... + 7593.

It is an arithmetic number, because the mean of its divisors is an integer number (7013625).

Almost surely, 2^28042481 is an apocalyptic number.

It is an amenable number.

28042481 is a deficient number, since it is larger than the sum of its proper divisors (12019).

28042481 is an equidigital number, since it uses as much as digits as its factorization.

28042481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12018.

The product of its (nonzero) digits is 4096, while the sum is 29.

The square root of 28042481 is about 5295.5151779596. The cubic root of 28042481 is about 303.8123878468.

The spelling of 28042481 in words is "twenty-eight million, forty-two thousand, four hundred eighty-one".