28677857 has 4 divisors (see below), whose sum is σ = 30883860. Its totient is φ = 26471856.

The previous prime is 28677841. The next prime is 28677863. The reversal of 28677857 is 75877682.

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 2217121 + 26460736 = 1489^2 + 5144^2 .

It is a cyclic number.

It is not a de Polignac number, because 28677857 - 2⁴ = 28677841 is a prime.

It is a super-2 number, since 2×28677857² = 1644838964224898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28677877) 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, 1102982 + ... + 1103007.

It is an arithmetic number, because the mean of its divisors is an integer number (7720965).

Almost surely, 2^28677857 is an apocalyptic number.

It is an amenable number.

28677857 is a deficient number, since it is larger than the sum of its proper divisors (2206003).

28677857 is a wasteful number, since it uses less digits than its factorization.

28677857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2206002.

The product of its digits is 1317120, while the sum is 50.

The square root of 28677857 is about 5355.1710523568. The cubic root of 28677857 is about 306.0898286690.

The spelling of 28677857 in words is "twenty-eight million, six hundred seventy-seven thousand, eight hundred fifty-seven".