66776317 has 4 divisors (see below), whose sum is σ = 70290880. Its totient is φ = 63261756.

The previous prime is 66776309. The next prime is 66776321. The reversal of 66776317 is 71367766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66776317 - 2³ = 66776309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66776327) 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, 1757253 + ... + 1757290.

It is an arithmetic number, because the mean of its divisors is an integer number (17572720).

Almost surely, 2^66776317 is an apocalyptic number.

It is an amenable number.

66776317 is a deficient number, since it is larger than the sum of its proper divisors (3514563).

66776317 is a wasteful number, since it uses less digits than its factorization.

66776317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3514562.

The product of its digits is 222264, while the sum is 43.

The square root of 66776317 is about 8171.6777347127. The cubic root of 66776317 is about 405.7023164290.

The spelling of 66776317 in words is "sixty-six million, seven hundred seventy-six thousand, three hundred seventeen".