217185960973 has 2 divisors, whose sum is σ = 217185960974.
Its totient is φ = 217185960972.
The previous prime is 217185960923. The next prime is 217185960977. The reversal of 217185960973 is 379069581712.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 197005485609 + 20180475364 = 443853^2 + 142058^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-217185960973 is a prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (217185960977) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108592980486 + 108592980487.
It is an arithmetic number, because the mean of its divisors is an integer number (108592980487).
Almost surely, 2217185960973 is an apocalyptic number.
It is an amenable number.
217185960973 is a deficient number, since it is larger than the sum of its proper divisors (1).
217185960973 is an equidigital number, since it uses as much as digits as its factorization.
217185960973 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 5715360, while the sum is 58.
The spelling of 217185960973 in words is "two hundred seventeen billion, one hundred eighty-five million, nine hundred sixty thousand, nine hundred seventy-three".