866027720667 has 4 divisors (see below), whose sum is σ = 1154703627560. Its totient is φ = 577351813776.

The previous prime is 866027720651. The next prime is 866027720711. The reversal of 866027720667 is 766027720668.

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

It is not a de Polignac number, because 866027720667 - 2⁴ = 866027720651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866027720267) 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, 144337953442 + ... + 144337953447.

It is an arithmetic number, because the mean of its divisors is an integer number (288675906890).

Almost surely, 2^866027720667 is an apocalyptic number.

866027720667 is a deficient number, since it is larger than the sum of its proper divisors (288675906893).

866027720667 is a wasteful number, since it uses less digits than its factorization.

866027720667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288675906892.

The product of its (nonzero) digits is 14224896, while the sum is 57.

Subtracting from 866027720667 its reverse (766027720668), we obtain a palindrome (99999999999).

The spelling of 866027720667 in words is "eight hundred sixty-six billion, twenty-seven million, seven hundred twenty thousand, six hundred sixty-seven".