7841668817664 has 864 divisors, whose sum is σ = 27654003336960. Its totient is φ = 2190219264000.

The previous prime is 7841668817611. The next prime is 7841668817669. The reversal of 7841668817664 is 4667188661487.

7841668817664 is a `hidden beast` number, since 7 + 8 + 416 + 6 + 8 + 81 + 76 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a super-2 number, since 2×7841668817664² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 7841668817592 and 7841668817601.

It is not an unprimeable number, because it can be changed into a prime (7841668817669) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 481046314 + ... + 481062614.

Almost surely, 2^{7841668817664} is an apocalyptic number.

7841668817664 is a gapful number since it is divisible by the number (74) 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 7841668817664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13827001668480).

7841668817664 is an abundant number, since it is smaller than the sum of its proper divisors (19812334519296).

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

7841668817664 is a wasteful number, since it uses less digits than its factorization.

7841668817664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16399 (or 16373 counting only the distinct ones).

The product of its digits is 520224768, while the sum is 72.

The spelling of 7841668817664 in words is "seven trillion, eight hundred forty-one billion, six hundred sixty-eight million, eight hundred seventeen thousand, six hundred sixty-four".