66531661345111 has 8 divisors (see below), whose sum is σ = 66797365585104. Its totient is φ = 66265962168000.

The previous prime is 66531661345087. The next prime is 66531661345117. The reversal of 66531661345111 is 11154316613566.

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

It is a cyclic number.

It is not a de Polignac number, because 66531661345111 - 2⁷ = 66531661344983 is a prime.

It is a super-2 number, since 2×66531661345111² (a number of 28 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 (66531661345117) 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, 26261835 + ... + 28683571.

It is an arithmetic number, because the mean of its divisors is an integer number (8349670698138).

Almost surely, 2^{66531661345111} is an apocalyptic number.

66531661345111 is a deficient number, since it is larger than the sum of its proper divisors (265704239993).

66531661345111 is a wasteful number, since it uses less digits than its factorization.

66531661345111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2531441.

The product of its digits is 1166400, while the sum is 49.

Adding to 66531661345111 its reverse (11154316613566), we get a palindrome (77685977958677).

The spelling of 66531661345111 in words is "sixty-six trillion, five hundred thirty-one billion, six hundred sixty-one million, three hundred forty-five thousand, one hundred eleven".