28321727 has 4 divisors (see below), whose sum is σ = 32367696. Its totient is φ = 24275760.

The previous prime is 28321721. The next prime is 28321729. The reversal of 28321727 is 72712382.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 72712382 = 2 ⋅36356191.

It is a cyclic number.

It is not a de Polignac number, because 28321727 - 2⁸ = 28321471 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28321693 and 28321702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2022974 + ... + 2022987.

It is an arithmetic number, because the mean of its divisors is an integer number (8091924).

Almost surely, 2^28321727 is an apocalyptic number.

28321727 is a deficient number, since it is larger than the sum of its proper divisors (4045969).

28321727 is an equidigital number, since it uses as much as digits as its factorization.

28321727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4045968.

The product of its digits is 9408, while the sum is 32.

The square root of 28321727 is about 5321.8161373727. The cubic root of 28321727 is about 304.8175097523.

The spelling of 28321727 in words is "twenty-eight million, three hundred twenty-one thousand, seven hundred twenty-seven".