66315646543 has 4 divisors (see below), whose sum is σ = 66924047080. Its totient is φ = 65707246008.

The previous prime is 66315646487. The next prime is 66315646571. The reversal of 66315646543 is 34564651366.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66315646543 - 2³³ = 57725711951 is a prime.

It is a super-2 number, since 2×66315646543² (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 (66315646343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304200105 + ... + 304200322.

It is an arithmetic number, because the mean of its divisors is an integer number (16731011770).

Almost surely, 2^66315646543 is an apocalyptic number.

66315646543 is a deficient number, since it is larger than the sum of its proper divisors (608400537).

66315646543 is a wasteful number, since it uses less digits than its factorization.

66315646543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608400536.

The product of its digits is 4665600, while the sum is 49.

The spelling of 66315646543 in words is "sixty-six billion, three hundred fifteen million, six hundred forty-six thousand, five hundred forty-three".