656778877656 has 256 divisors, whose sum is σ = 1870435929600. Its totient is φ = 190425600000.

The previous prime is 656778877627. The next prime is 656778877661.

656778877656 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 345490306 + ... + 345492206.

It is an arithmetic number, because the mean of its divisors is an integer number (7306390350).

Almost surely, 2^656778877656 is an apocalyptic number.

656778877656 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 656778877656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (935217964800).

656778877656 is an abundant number, since it is smaller than the sum of its proper divisors (1213657051944).

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

656778877656 is a wasteful number, since it uses less digits than its factorization.

656778877656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2562 (or 2558 counting only the distinct ones).

The product of its digits is 4978713600, while the sum is 78.

The spelling of 656778877656 in words is "six hundred fifty-six billion, seven hundred seventy-eight million, eight hundred seventy-seven thousand, six hundred fifty-six".