66000001 has 4 divisors (see below), whose sum is σ = 69882372. Its totient is φ = 62117632.

The previous prime is 65999993. The next prime is 66000007. The reversal of 66000001 is 10000066.

66000001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 51552400 + 14447601 = 7180^2 + 3801^2 .

It is a cyclic number.

It is not a de Polignac number, because 66000001 - 2³ = 65999993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66000007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1941160 + ... + 1941193.

It is an arithmetic number, because the mean of its divisors is an integer number (17470593).

Almost surely, 2^66000001 is an apocalyptic number.

It is an amenable number.

66000001 is a deficient number, since it is larger than the sum of its proper divisors (3882371).

66000001 is a wasteful number, since it uses less digits than its factorization.

66000001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3882370.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 66000001 is about 8124.0384661817. The cubic root of 66000001 is about 404.1240041032.

Adding to 66000001 its reverse (10000066), we get a palindrome (76000067).

The spelling of 66000001 in words is "sixty-six million, one", and thus it is an aban number and an uban number.