66491147 has 2 divisors, whose sum is σ = 66491148. Its totient is φ = 66491146.

The previous prime is 66491107. The next prime is 66491153. The reversal of 66491147 is 74119466.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66491147 - 2⁶ = 66491083 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66491147.

It is not a weakly prime, because it can be changed into another prime (66491107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33245573 + 33245574.

It is an arithmetic number, because the mean of its divisors is an integer number (33245574).

Almost surely, 2^66491147 is an apocalyptic number.

66491147 is a deficient number, since it is larger than the sum of its proper divisors (1).

66491147 is an equidigital number, since it uses as much as digits as its factorization.

66491147 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 38.

The square root of 66491147 is about 8154.2103848257. The cubic root of 66491147 is about 405.1239715995.

The spelling of 66491147 in words is "sixty-six million, four hundred ninety-one thousand, one hundred forty-seven".