217428763 has 2 divisors, whose sum is σ = 217428764. Its totient is φ = 217428762.

The previous prime is 217428749. The next prime is 217428803. The reversal of 217428763 is 367824712.

It is an a-pointer prime, because the next prime (217428803) can be obtained adding 217428763 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217428763 is a prime.

It is not a weakly prime, because it can be changed into another prime (217428713) 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, 108714381 + 108714382.

It is an arithmetic number, because the mean of its divisors is an integer number (108714382).

Almost surely, 2^217428763 is an apocalyptic number.

217428763 is a deficient number, since it is larger than the sum of its proper divisors (1).

217428763 is an equidigital number, since it uses as much as digits as its factorization.

217428763 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 112896, while the sum is 40.

The square root of 217428763 is about 14745.4658454726. The cubic root of 217428763 is about 601.3200224751.

The spelling of 217428763 in words is "two hundred seventeen million, four hundred twenty-eight thousand, seven hundred sixty-three".