6640169400 has 768 divisors, whose sum is σ = 26355456000. Its totient is φ = 1545246720.

The previous prime is 6640169387. The next prime is 6640169401. The reversal of 6640169400 is 49610466.

6640169400 is a `hidden beast` number, since 6 + 640 + 1 + 6 + 9 + 4 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640169401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 141280177 + ... + 141280223.

It is an arithmetic number, because the mean of its divisors is an integer number (34317000).

Almost surely, 2^6640169400 is an apocalyptic number.

6640169400 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 6640169400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13177728000).

6640169400 is an abundant number, since it is smaller than the sum of its proper divisors (19715286600).

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

6640169400 is a wasteful number, since it uses less digits than its factorization.

6640169400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 6640169400 is about 81487.2345830928. The cubic root of 6640169400 is about 1879.5752586569.

Adding to 6640169400 its reverse (49610466), we get a palindrome (6689779866).

The spelling of 6640169400 in words is "six billion, six hundred forty million, one hundred sixty-nine thousand, four hundred".