66000066 has 32 divisors (see below), whose sum is σ = 145440576. Its totient is φ = 19800000.

The previous prime is 66000049. The next prime is 66000071.

66000066 is nontrivially palindromic in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1716 + ... + 11616.

It is an arithmetic number, because the mean of its divisors is an integer number (4545018).

Almost surely, 2^66000066 is an apocalyptic number.

66000066 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 66000066, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72720288).

66000066 is an abundant number, since it is smaller than the sum of its proper divisors (79440510).

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

66000066 is a wasteful number, since it uses less digits than its factorization.

66000066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10018.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 66000066 is about 8124.0424666541. The cubic root of 66000066 is about 404.1241367702.

It can be divided in two parts, 660000 and 66, that multiplied together give a square (43560000 = 6600²).

The spelling of 66000066 in words is "sixty-six million, sixty-six", and thus it is an aban number, an eban number, and an uban number.