66105552100 has 81 divisors (see below), whose sum is σ = 166914744507. Its totient is φ = 22658590080.

The previous prime is 66105552083. The next prime is 66105552101. The reversal of 66105552100 is 125550166.

The square root of 66105552100 is 257110.

It is a perfect power (a square), and thus also a powerful number.

66105552100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 25485568164 + 40619983936 = 159642^2 + 201544^2 .

It is not an unprimeable number, because it can be changed into a prime (66105552101) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 17995864 + ... + 17999536.

Almost surely, 2^66105552100 is an apocalyptic number.

66105552100 is the 257110-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66105552100

66105552100 is an abundant number, since it is smaller than the sum of its proper divisors (100809192407).

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

66105552100 is an equidigital number, since it uses as much as digits as its factorization.

66105552100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7374 (or 3687 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 31.

The spelling of 66105552100 in words is "sixty-six billion, one hundred five million, five hundred fifty-two thousand, one hundred".