656994380477760 has 896 divisors, whose sum is σ = 2548164624768000. Its totient is φ = 158373543444480.

The previous prime is 656994380477723. The next prime is 656994380477803. The reversal of 656994380477760 is 67774083499656.

656994380477760 is a `hidden beast` number, since 6 + 5 + 6 + 9 + 9 + 4 + 3 + 80 + 477 + 7 + 60 = 666.

It is a Smith number, since the sum of its digits (81) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 656994380477760.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1187956822 + ... + 1188509738.

It is an arithmetic number, because the mean of its divisors is an integer number (2843933733000).

Almost surely, 2^{656994380477760} is an apocalyptic number.

656994380477760 is a gapful number since it is divisible by the number (60) 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 656994380477760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1274082312384000).

656994380477760 is an abundant number, since it is smaller than the sum of its proper divisors (1891170244290240).

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

656994380477760 is a wasteful number, since it uses less digits than its factorization.

656994380477760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553176 (or 553160 counting only the distinct ones).

The product of its (nonzero) digits is 11522165760, while the sum is 81.

The spelling of 656994380477760 in words is "six hundred fifty-six trillion, nine hundred ninety-four billion, three hundred eighty million, four hundred seventy-seven thousand, seven hundred sixty".