656879978656 has 96 divisors (see below), whose sum is σ = 1492305752448. Its totient is φ = 281687408640.

The previous prime is 656879978653. The next prime is 656879978659.

656879978656 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (656879978653) and next prime (656879978659).

It is a self number, because there is not a number n which added to its sum of digits gives 656879978656.

It is not an unprimeable number, because it can be changed into a prime (656879978653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35280 + ... + 1146736.

It is an arithmetic number, because the mean of its divisors is an integer number (15544851588).

Almost surely, 2^656879978656 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 656879978656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (746152876224).

656879978656 is an abundant number, since it is smaller than the sum of its proper divisors (835425773792).

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

656879978656 is a wasteful number, since it uses less digits than its factorization.

656879978656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111574 (or 1111566 counting only the distinct ones).

The product of its digits is 8230118400, while the sum is 82.

The spelling of 656879978656 in words is "six hundred fifty-six billion, eight hundred seventy-nine million, nine hundred seventy-eight thousand, six hundred fifty-six".