77844868668 has 192 divisors, whose sum is σ = 234884966400. Its totient is φ = 21834593280.

The previous prime is 77844868547. The next prime is 77844868721. The reversal of 77844868668 is 86686844877.

77844868668 is a `hidden beast` number, since 7 + 7 + 8 + 4 + 486 + 86 + 68 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 77844868596 and 77844868605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 29835748 + ... + 29838356.

It is an arithmetic number, because the mean of its divisors is an integer number (1223359200).

Almost surely, 2^77844868668 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 77844868668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117442483200).

77844868668 is an abundant number, since it is smaller than the sum of its proper divisors (157040097732).

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

77844868668 is a wasteful number, since it uses less digits than its factorization.

77844868668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3337 (or 3329 counting only the distinct ones).

The product of its digits is 693633024, while the sum is 72.

The spelling of 77844868668 in words is "seventy-seven billion, eight hundred forty-four million, eight hundred sixty-eight thousand, six hundred sixty-eight".