28128677 has 4 divisors (see below), whose sum is σ = 28548576. Its totient is φ = 27708780.

The previous prime is 28128671. The next prime is 28128689. The reversal of 28128677 is 77682182.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28128677 - 2⁶ = 28128613 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 (28128671) 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, 209849 + ... + 209982.

It is an arithmetic number, because the mean of its divisors is an integer number (7137144).

Almost surely, 2^28128677 is an apocalyptic number.

It is an amenable number.

28128677 is a deficient number, since it is larger than the sum of its proper divisors (419899).

28128677 is an equidigital number, since it uses as much as digits as its factorization.

28128677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 419898.

The product of its digits is 75264, while the sum is 41.

The square root of 28128677 is about 5303.6475184537. The cubic root of 28128677 is about 304.1233520940.

The spelling of 28128677 in words is "twenty-eight million, one hundred twenty-eight thousand, six hundred seventy-seven".