28128087 has 32 divisors (see below), whose sum is σ = 45301760. Its totient is φ = 17146080.

The previous prime is 28128083. The next prime is 28128101. The reversal of 28128087 is 78082182.

It is not a de Polignac number, because 28128087 - 2² = 28128083 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28128083) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44262 + ... + 44892.

It is an arithmetic number, because the mean of its divisors is an integer number (1415680).

Almost surely, 2^28128087 is an apocalyptic number.

28128087 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

28128087 is a deficient number, since it is larger than the sum of its proper divisors (17173673).

28128087 is a wasteful number, since it uses less digits than its factorization.

28128087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780 (or 774 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 36.

The square root of 28128087 is about 5303.5918960644. The cubic root of 28128087 is about 304.1212257465.

Subtracting from 28128087 its product of nonzero digits (14336), we obtain a triangular number (28113751 = T₇₄₉₈).

The spelling of 28128087 in words is "twenty-eight million, one hundred twenty-eight thousand, eighty-seven".