66311791 has 8 divisors (see below), whose sum is σ = 81614624. Its totient is φ = 52466400.

The previous prime is 66311779. The next prime is 66311797. The reversal of 66311791 is 19711366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66311791 - 2⁹ = 66311279 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66311797) by changing a digit.

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, 364260 + ... + 364441.

It is an arithmetic number, because the mean of its divisors is an integer number (10201828).

Almost surely, 2^66311791 is an apocalyptic number.

66311791 is a deficient number, since it is larger than the sum of its proper divisors (15302833).

66311791 is a wasteful number, since it uses less digits than its factorization.

66311791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728721.

The product of its digits is 6804, while the sum is 34.

The square root of 66311791 is about 8143.2052043406. The cubic root of 66311791 is about 404.7593774656.

The spelling of 66311791 in words is "sixty-six million, three hundred eleven thousand, seven hundred ninety-one".