28089765 has 24 divisors (see below), whose sum is σ = 53116128. Its totient is φ = 13619040.

The previous prime is 28089713. The next prime is 28089767. The reversal of 28089765 is 56798082.

It is not a de Polignac number, because 28089765 - 2⁶ = 28089701 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 28089765.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28089767) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27879 + ... + 28868.

It is an arithmetic number, because the mean of its divisors is an integer number (2213172).

Almost surely, 2^28089765 is an apocalyptic number.

It is an amenable number.

28089765 is a deficient number, since it is larger than the sum of its proper divisors (25026363).

28089765 is a wasteful number, since it uses less digits than its factorization.

28089765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56769 (or 56766 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 28089765 is about 5299.9778301423. The cubic root of 28089765 is about 303.9830503304.

The spelling of 28089765 in words is "twenty-eight million, eighty-nine thousand, seven hundred sixty-five".