66976691 has 6 divisors (see below), whose sum is σ = 70687692. Its totient is φ = 63451260.

The previous prime is 66976687. The next prime is 66976703. The reversal of 66976691 is 19667966.

It is a happy number.

It is not a de Polignac number, because 66976691 - 2² = 66976687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66976681) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92405 + ... + 93126.

It is an arithmetic number, because the mean of its divisors is an integer number (11781282).

Almost surely, 2^66976691 is an apocalyptic number.

66976691 is a deficient number, since it is larger than the sum of its proper divisors (3711001).

66976691 is a wasteful number, since it uses less digits than its factorization.

66976691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185569 (or 185550 counting only the distinct ones).

The product of its digits is 734832, while the sum is 50.

The square root of 66976691 is about 8183.9288242262. The cubic root of 66976691 is about 406.1077047683.

The spelling of 66976691 in words is "sixty-six million, nine hundred seventy-six thousand, six hundred ninety-one".