66880947191 has 4 divisors (see below), whose sum is σ = 66881470032. Its totient is φ = 66880424352.

The previous prime is 66880947163. The next prime is 66880947193. The reversal of 66880947191 is 19174908866.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66880947191 is a prime.

It is a super-2 number, since 2×66880947191² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66880947191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66880947193) 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, 73406 + ... + 373028.

It is an arithmetic number, because the mean of its divisors is an integer number (16720367508).

Almost surely, 2^66880947191 is an apocalyptic number.

66880947191 is a deficient number, since it is larger than the sum of its proper divisors (522841).

66880947191 is a wasteful number, since it uses less digits than its factorization.

66880947191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522840.

The product of its (nonzero) digits is 5225472, while the sum is 59.

The spelling of 66880947191 in words is "sixty-six billion, eight hundred eighty million, nine hundred forty-seven thousand, one hundred ninety-one".