66641295971 has 4 divisors (see below), whose sum is σ = 66693483072. Its totient is φ = 66589108872.

The previous prime is 66641295949. The next prime is 66641296021. The reversal of 66641295971 is 17959214666.

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 66641295971 - 2⁶ = 66641295907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66641205971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26091635 + ... + 26094188.

It is an arithmetic number, because the mean of its divisors is an integer number (16673370768).

Almost surely, 2^66641295971 is an apocalyptic number.

66641295971 is a deficient number, since it is larger than the sum of its proper divisors (52187101).

66641295971 is a wasteful number, since it uses less digits than its factorization.

66641295971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52187100.

The product of its digits is 4898880, while the sum is 56.

The spelling of 66641295971 in words is "sixty-six billion, six hundred forty-one million, two hundred ninety-five thousand, nine hundred seventy-one".