28666865831843 has 4 divisors (see below), whose sum is σ = 28666891715568. Its totient is φ = 28666839948120.

The previous prime is 28666865831713. The next prime is 28666865831899. The reversal of 28666865831843 is 34813856866682.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28666865831843 - 2³² = 28662570864547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28666865831543) 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, 11202668 + ... + 13521593.

It is an arithmetic number, because the mean of its divisors is an integer number (7166722928892).

Almost surely, 2^{28666865831843} is an apocalyptic number.

28666865831843 is a deficient number, since it is larger than the sum of its proper divisors (25883725).

28666865831843 is a wasteful number, since it uses less digits than its factorization.

28666865831843 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25883724.

The product of its digits is 1911029760, while the sum is 74.

The spelling of 28666865831843 in words is "twenty-eight trillion, six hundred sixty-six billion, eight hundred sixty-five million, eight hundred thirty-one thousand, eight hundred forty-three".