66345064781 has 8 divisors (see below), whose sum is σ = 67803816960. Its totient is φ = 64888277488.

The previous prime is 66345064763. The next prime is 66345064787. The reversal of 66345064781 is 18746054366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66345064781 is a prime.

It is a super-2 number, since 2×66345064781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66345064787) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 422846 + ... + 558111.

It is an arithmetic number, because the mean of its divisors is an integer number (8475477120).

Almost surely, 2^66345064781 is an apocalyptic number.

It is an amenable number.

66345064781 is a deficient number, since it is larger than the sum of its proper divisors (1458752179).

66345064781 is a wasteful number, since it uses less digits than its factorization.

66345064781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 982443.

The product of its (nonzero) digits is 2903040, while the sum is 50.

The spelling of 66345064781 in words is "sixty-six billion, three hundred forty-five million, sixty-four thousand, seven hundred eighty-one".