28187128 has 8 divisors (see below), whose sum is σ = 52850880. Its totient is φ = 14093560.

The previous prime is 28187123. The next prime is 28187129. The reversal of 28187128 is 82178182.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28187123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1761688 + ... + 1761703.

It is an arithmetic number, because the mean of its divisors is an integer number (6606360).

Almost surely, 2^28187128 is an apocalyptic number.

It is an amenable number.

28187128 is a deficient number, since it is larger than the sum of its proper divisors (24663752).

28187128 is a wasteful number, since it uses less digits than its factorization.

28187128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3523397 (or 3523393 counting only the distinct ones).

The product of its digits is 14336, while the sum is 37.

The square root of 28187128 is about 5309.1551116915. The cubic root of 28187128 is about 304.3338610498. Note that the first 3 decimals are identical.

The spelling of 28187128 in words is "twenty-eight million, one hundred eighty-seven thousand, one hundred twenty-eight".