28487457 has 20 divisors (see below), whose sum is σ = 43550320. Its totient is φ = 18547704.

The previous prime is 28487449. The next prime is 28487471. The reversal of 28487457 is 75478482.

It is not a de Polignac number, because 28487457 - 2³ = 28487449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28488457) 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 19 ways as a sum of consecutive naturals, for example, 607 + ... + 7572.

It is an arithmetic number, because the mean of its divisors is an integer number (2177516).

Almost surely, 2^28487457 is an apocalyptic number.

28487457 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28487457 is a deficient number, since it is larger than the sum of its proper divisors (15062863).

28487457 is an equidigital number, since it uses as much as digits as its factorization.

28487457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8234 (or 8225 counting only the distinct ones).

The product of its digits is 501760, while the sum is 45.

The square root of 28487457 is about 5337.3642371493. The cubic root of 28487457 is about 305.4109197465.

Subtracting 28487457 from its reverse (75478482), we obtain a square (46991025 = 6855²).

The spelling of 28487457 in words is "twenty-eight million, four hundred eighty-seven thousand, four hundred fifty-seven".