66681020201 has 16 divisors (see below), whose sum is σ = 74468520000. Its totient is φ = 59336229888.

The previous prime is 66681020183. The next prime is 66681020249. The reversal of 66681020201 is 10202018666.

It is not a de Polignac number, because 66681020201 - 2³⁰ = 65607278377 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66681020291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45680 + ... + 368033.

It is an arithmetic number, because the mean of its divisors is an integer number (4654282500).

Almost surely, 2^66681020201 is an apocalyptic number.

It is an amenable number.

66681020201 is a deficient number, since it is larger than the sum of its proper divisors (7787499799).

66681020201 is a wasteful number, since it uses less digits than its factorization.

66681020201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414248.

The product of its (nonzero) digits is 6912, while the sum is 32.

Adding to 66681020201 its reverse (10202018666), we get a palindrome (76883038867).

The spelling of 66681020201 in words is "sixty-six billion, six hundred eighty-one million, twenty thousand, two hundred one".