217728001 has 2 divisors, whose sum is σ = 217728002. Its totient is φ = 217728000.

The previous prime is 217727953. The next prime is 217728037. The reversal of 217728001 is 100827712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200958976 + 16769025 = 14176^2 + 4095^2 .

It is a cyclic number.

It is not a de Polignac number, because 217728001 - 2¹³ = 217719809 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (217728041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108864000 + 108864001.

It is an arithmetic number, because the mean of its divisors is an integer number (108864001).

Almost surely, 2^217728001 is an apocalyptic number.

It is an amenable number.

217728001 is a deficient number, since it is larger than the sum of its proper divisors (1).

217728001 is an equidigital number, since it uses as much as digits as its factorization.

217728001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 217728001 is about 14755.6091368672. The cubic root of 217728001 is about 601.5957531168.

The spelling of 217728001 in words is "two hundred seventeen million, seven hundred twenty-eight thousand, one".