28124765 has 4 divisors (see below), whose sum is σ = 33749724. Its totient is φ = 22499808.

The previous prime is 28124717. The next prime is 28124771. The reversal of 28124765 is 56742182.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13271449 + 14853316 = 3643^2 + 3854^2 .

It is a cyclic number.

It is not a de Polignac number, because 28124765 - 2²² = 23930461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2812472 + ... + 2812481.

It is an arithmetic number, because the mean of its divisors is an integer number (8437431).

Almost surely, 2^28124765 is an apocalyptic number.

It is an amenable number.

28124765 is a deficient number, since it is larger than the sum of its proper divisors (5624959).

28124765 is an equidigital number, since it uses as much as digits as its factorization.

28124765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5624958.

The product of its digits is 26880, while the sum is 35.

The square root of 28124765 is about 5303.2787028403. The cubic root of 28124765 is about 304.1092527734.

The spelling of 28124765 in words is "twenty-eight million, one hundred twenty-four thousand, seven hundred sixty-five".