217136947 has 2 divisors, whose sum is σ = 217136948. Its totient is φ = 217136946.

The previous prime is 217136929. The next prime is 217136963. The reversal of 217136947 is 749631712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 217136947 - 2¹¹ = 217134899 is a prime.

It is not a weakly prime, because it can be changed into another prime (217136977) 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, 108568473 + 108568474.

It is an arithmetic number, because the mean of its divisors is an integer number (108568474).

Almost surely, 2^217136947 is an apocalyptic number.

217136947 is a deficient number, since it is larger than the sum of its proper divisors (1).

217136947 is an equidigital number, since it uses as much as digits as its factorization.

217136947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 40.

The square root of 217136947 is about 14735.5674135745. The cubic root of 217136947 is about 601.0508870232.

The spelling of 217136947 in words is "two hundred seventeen million, one hundred thirty-six thousand, nine hundred forty-seven".