28668683857 has 4 divisors (see below), whose sum is σ = 31274927856. Its totient is φ = 26062439860.

The previous prime is 28668683851. The next prime is 28668683863. The reversal of 28668683857 is 75838686682.

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 an interprime number because it is at equal distance from previous prime (28668683851) and next prime (28668683863).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28668683857 is a prime.

It is a super-2 number, since 2×28668683857² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28668683792 and 28668683801.

It is not an unprimeable number, because it can be changed into a prime (28668683851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1303121983 + ... + 1303122004.

It is an arithmetic number, because the mean of its divisors is an integer number (7818731964).

Almost surely, 2^28668683857 is an apocalyptic number.

It is an amenable number.

28668683857 is a deficient number, since it is larger than the sum of its proper divisors (2606243999).

28668683857 is a wasteful number, since it uses less digits than its factorization.

28668683857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2606243998.

The product of its digits is 185794560, while the sum is 67.

The spelling of 28668683857 in words is "twenty-eight billion, six hundred sixty-eight million, six hundred eighty-three thousand, eight hundred fifty-seven".