866508216780887 has 4 divisors (see below), whose sum is σ = 872833094275776. Its totient is φ = 860183339286000.

The previous prime is 866508216780853. The next prime is 866508216780919. The reversal of 866508216780887 is 788087612805668.

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 866508216780887 - 2⁶ = 866508216780823 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 (866508216780827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3162438747239 + ... + 3162438747512.

It is an arithmetic number, because the mean of its divisors is an integer number (218208273568944).

Almost surely, 2^{866508216780887} is an apocalyptic number.

866508216780887 is a deficient number, since it is larger than the sum of its proper divisors (6324877494889).

866508216780887 is a wasteful number, since it uses less digits than its factorization.

866508216780887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6324877494888.

The product of its (nonzero) digits is 3468165120, while the sum is 80.

The spelling of 866508216780887 in words is "eight hundred sixty-six trillion, five hundred eight billion, two hundred sixteen million, seven hundred eighty thousand, eight hundred eighty-seven".