66111312645021 has 8 divisors (see below), whose sum is σ = 100741047840064. Its totient is φ = 37777892940000.

The previous prime is 66111312644987. The next prime is 66111312645089. The reversal of 66111312645021 is 12054621311166.

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

It is not a de Polignac number, because 66111312645021 - 2¹⁸ = 66111312382877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66111312647021) 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, 1574078872480 + ... + 1574078872521.

It is an arithmetic number, because the mean of its divisors is an integer number (12592630980008).

Almost surely, 2^{66111312645021} is an apocalyptic number.

It is an amenable number.

66111312645021 is a deficient number, since it is larger than the sum of its proper divisors (34629735195043).

66111312645021 is a wasteful number, since it uses less digits than its factorization.

66111312645021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3148157745011.

The product of its (nonzero) digits is 51840, while the sum is 39.

Adding to 66111312645021 its reverse (12054621311166), we get a palindrome (78165933956187).

The spelling of 66111312645021 in words is "sixty-six trillion, one hundred eleven billion, three hundred twelve million, six hundred forty-five thousand, twenty-one".