6665921136 has 320 divisors, whose sum is σ = 23358504960. Its totient is φ = 1776660480.

The previous prime is 6665921099. The next prime is 6665921137. The reversal of 6665921136 is 6311295666.

It is a junction number, because it is equal to n+sod(n) for n = 6665921091 and 6665921100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6665921137) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6528306 + ... + 6529326.

It is an arithmetic number, because the mean of its divisors is an integer number (72995328).

Almost surely, 2^6665921136 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 6665921136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11679252480).

6665921136 is an abundant number, since it is smaller than the sum of its proper divisors (16692583824).

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

6665921136 is a wasteful number, since it uses less digits than its factorization.

6665921136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189 (or 1177 counting only the distinct ones).

The product of its digits is 349920, while the sum is 45.

The square root of 6665921136 is about 81645.0925408257. The cubic root of 6665921136 is about 1882.0018980249.

The spelling of 6665921136 in words is "six billion, six hundred sixty-five million, nine hundred twenty-one thousand, one hundred thirty-six".