66869582991 has 4 divisors (see below), whose sum is σ = 89159443992. Its totient is φ = 44579721992.

The previous prime is 66869582987. The next prime is 66869583007. The reversal of 66869582991 is 19928596866.

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 66869582991 - 2² = 66869582987 is a prime.

It is a super-2 number, since 2×66869582991² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66869582921) 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, 11144930496 + ... + 11144930501.

It is an arithmetic number, because the mean of its divisors is an integer number (22289860998).

Almost surely, 2^66869582991 is an apocalyptic number.

66869582991 is a deficient number, since it is larger than the sum of its proper divisors (22289861001).

66869582991 is a wasteful number, since it uses less digits than its factorization.

66869582991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22289861000.

The product of its digits is 100776960, while the sum is 69.

The spelling of 66869582991 in words is "sixty-six billion, eight hundred sixty-nine million, five hundred eighty-two thousand, nine hundred ninety-one".