28505144 has 16 divisors (see below), whose sum is σ = 55290600. Its totient is φ = 13760992.

The previous prime is 28505093. The next prime is 28505153. The reversal of 28505144 is 44150582.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is an unprimeable number.

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, 61202 + ... + 61665.

Almost surely, 2^28505144 is an apocalyptic number.

It is an amenable number.

28505144 is a deficient number, since it is larger than the sum of its proper divisors (26785456).

28505144 is a wasteful number, since it uses less digits than its factorization.

28505144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122902 (or 122898 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 29.

The square root of 28505144 is about 5339.0208840198. The cubic root of 28505144 is about 305.4741134693.

The spelling of 28505144 in words is "twenty-eight million, five hundred five thousand, one hundred forty-four".