66681671395 has 8 divisors (see below), whose sum is σ = 82180654704. Its totient is φ = 51903571104.

The previous prime is 66681671339. The next prime is 66681671411. The reversal of 66681671395 is 59317618666.

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-66681671395 is a prime.

It is a super-2 number, since 2×66681671395² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180220549 + ... + 180220918.

It is an arithmetic number, because the mean of its divisors is an integer number (10272581838).

Almost surely, 2^66681671395 is an apocalyptic number.

66681671395 is a deficient number, since it is larger than the sum of its proper divisors (15498983309).

66681671395 is a wasteful number, since it uses less digits than its factorization.

66681671395 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360441509.

The product of its digits is 9797760, while the sum is 58.

The spelling of 66681671395 in words is "sixty-six billion, six hundred eighty-one million, six hundred seventy-one thousand, three hundred ninety-five".