66601001 has 4 divisors (see below), whose sum is σ = 66630912. Its totient is φ = 66571092.

The previous prime is 66600991. The next prime is 66601009. The reversal of 66601001 is 10010666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66601001 - 2¹⁰ = 66599977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66601009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11321 + ... + 16166.

It is an arithmetic number, because the mean of its divisors is an integer number (16657728).

Almost surely, 2^66601001 is an apocalyptic number.

It is an amenable number.

66601001 is a deficient number, since it is larger than the sum of its proper divisors (29911).

66601001 is a wasteful number, since it uses less digits than its factorization.

66601001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29910.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 66601001 is about 8160.9436341639. The cubic root of 66601001 is about 405.3469586875.

Adding to 66601001 its reverse (10010666), we get a palindrome (76611667).

The spelling of 66601001 in words is "sixty-six million, six hundred one thousand, one".