866977779668 has 96 divisors (see below), whose sum is σ = 2038642249728. Its totient is φ = 311563324800.

The previous prime is 866977779667. The next prime is 866977779673.

866977779668 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 866977779668.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866977779667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5231723 + ... + 5394893.

It is an arithmetic number, because the mean of its divisors is an integer number (21235856768).

Almost surely, 2^866977779668 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 866977779668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1019321124864).

866977779668 is an abundant number, since it is smaller than the sum of its proper divisors (1171664470060).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866977779668 is a wasteful number, since it uses less digits than its factorization.

866977779668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164533 (or 164531 counting only the distinct ones).

The product of its digits is 16131032064, while the sum is 86.

The spelling of 866977779668 in words is "eight hundred sixty-six billion, nine hundred seventy-seven million, seven hundred seventy-nine thousand, six hundred sixty-eight".