66406326500 has 192 divisors, whose sum is σ = 159149914560. Its totient is φ = 24104960000.

The previous prime is 66406326499. The next prime is 66406326527. The reversal of 66406326500 is 562360466.

It can be written as a sum of positive squares in 32 ways, for example, as 64634926756 + 1771399744 = 254234^2 + 42088^2 .

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, 31015430 + ... + 31017570.

It is an arithmetic number, because the mean of its divisors is an integer number (828905805).

Almost surely, 2^66406326500 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 66406326500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79574957280).

66406326500 is an abundant number, since it is smaller than the sum of its proper divisors (92743588060).

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

66406326500 is a wasteful number, since it uses less digits than its factorization.

66406326500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2307 (or 2295 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 38.

Adding to 66406326500 its reverse (562360466), we get a palindrome (66968686966).

The spelling of 66406326500 in words is "sixty-six billion, four hundred six million, three hundred twenty-six thousand, five hundred".