217998073 has 2 divisors, whose sum is σ = 217998074. Its totient is φ = 217998072.

The previous prime is 217998061. The next prime is 217998119. The reversal of 217998073 is 370899712.

It is a happy number.

It is an a-pointer prime, because the next prime (217998119) can be obtained adding 217998073 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182034064 + 35964009 = 13492^2 + 5997^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217998073 is a prime.

It is not a weakly prime, because it can be changed into another prime (217996073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108999036 + 108999037.

It is an arithmetic number, because the mean of its divisors is an integer number (108999037).

Almost surely, 2^217998073 is an apocalyptic number.

It is an amenable number.

217998073 is a deficient number, since it is larger than the sum of its proper divisors (1).

217998073 is an equidigital number, since it uses as much as digits as its factorization.

217998073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 190512, while the sum is 46.

The square root of 217998073 is about 14764.7578036350. The cubic root of 217998073 is about 601.8443921458.

The spelling of 217998073 in words is "two hundred seventeen million, nine hundred ninety-eight thousand, seventy-three".