66690347 has 2 divisors, whose sum is σ = 66690348. Its totient is φ = 66690346.

The previous prime is 66690319. The next prime is 66690389. The reversal of 66690347 is 74309666.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66690347 - 2¹² = 66686251 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66690047) 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 as a sum of consecutive naturals, namely, 33345173 + 33345174.

It is an arithmetic number, because the mean of its divisors is an integer number (33345174).

Almost surely, 2^66690347 is an apocalyptic number.

66690347 is a deficient number, since it is larger than the sum of its proper divisors (1).

66690347 is an equidigital number, since it uses as much as digits as its factorization.

66690347 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 41.

The square root of 66690347 is about 8166.4157988679. The cubic root of 66690347 is about 405.5281368785.

The spelling of 66690347 in words is "sixty-six million, six hundred ninety thousand, three hundred forty-seven".