66712771 has 4 divisors (see below), whose sum is σ = 67708552. Its totient is φ = 65716992.

The previous prime is 66712769. The next prime is 66712783. The reversal of 66712771 is 17721766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17721766 = 2 ⋅8860883.

It is a cyclic number.

It is not a de Polignac number, because 66712771 - 2¹ = 66712769 is a prime.

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 66712771.

It is not an unprimeable number, because it can be changed into a prime (66712721) 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, 497790 + ... + 497923.

It is an arithmetic number, because the mean of its divisors is an integer number (16927138).

Almost surely, 2^66712771 is an apocalyptic number.

66712771 is a deficient number, since it is larger than the sum of its proper divisors (995781).

66712771 is an equidigital number, since it uses as much as digits as its factorization.

66712771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995780.

The product of its digits is 24696, while the sum is 37.

The square root of 66712771 is about 8167.7886236117. The cubic root of 66712771 is about 405.5735834553.

The spelling of 66712771 in words is "sixty-six million, seven hundred twelve thousand, seven hundred seventy-one".