666005100 has 144 divisors (see below), whose sum is σ = 2040286080. Its totient is φ = 167270400.

The previous prime is 666005029. The next prime is 666005149. The reversal of 666005100 is 1500666.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 1886524 + ... + 1886876.

Almost surely, 2^666005100 is an apocalyptic number.

666005100 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 666005100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1020143040).

666005100 is an abundant number, since it is smaller than the sum of its proper divisors (1374280980).

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

666005100 is a wasteful number, since it uses less digits than its factorization.

666005100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720 (or 713 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 666005100 is about 25807.0746114316. The cubic root of 666005100 is about 873.2914032404.

Adding to 666005100 its reverse (1500666), we get a palindrome (667505766).

The spelling of 666005100 in words is "six hundred sixty-six million, five thousand, one hundred".