666442200 has 96 divisors (see below), whose sum is σ = 2071296000. Its totient is φ = 177260160.

The previous prime is 666442199. The next prime is 666442207. The reversal of 666442200 is 2244666.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666442207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 276601 + ... + 278999.

It is an arithmetic number, because the mean of its divisors is an integer number (21576000).

Almost surely, 2^666442200 is an apocalyptic number.

666442200 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 666442200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1035648000).

666442200 is an abundant number, since it is smaller than the sum of its proper divisors (1404853800).

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

666442200 is a wasteful number, since it uses less digits than its factorization.

666442200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2881 (or 2872 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 30.

The square root of 666442200 is about 25815.5418304555. The cubic root of 666442200 is about 873.4824088828.

Adding to 666442200 its reverse (2244666), we get a palindrome (668686866).

The spelling of 666442200 in words is "six hundred sixty-six million, four hundred forty-two thousand, two hundred".