656505505656 has 1152 divisors, whose sum is σ = 2567593728000. Its totient is φ = 153871280640.

The previous prime is 656505505619. The next prime is 656505505661.

656505505656 is nontrivially palindromic in base 10.

656505505656 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 782485285 + ... + 782486123.

It is an arithmetic number, because the mean of its divisors is an integer number (2228814000).

Almost surely, 2^656505505656 is an apocalyptic number.

656505505656 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 656505505656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1283796864000).

656505505656 is an abundant number, since it is smaller than the sum of its proper divisors (1911088222344).

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

656505505656 is a wasteful number, since it uses less digits than its factorization.

656505505656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 950 (or 922 counting only the distinct ones).

The product of its (nonzero) digits is 20250000, while the sum is 54.

The spelling of 656505505656 in words is "six hundred fifty-six billion, five hundred five million, five hundred five thousand, six hundred fifty-six".