394377720017 has 2 divisors, whose sum is σ = 394377720018. Its totient is φ = 394377720016.

The previous prime is 394377720013. The next prime is 394377720019. The reversal of 394377720017 is 710027773493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 287595165841 + 106782554176 = 536279^2 + 326776^2 .

It is a cyclic number.

It is not a de Polignac number, because 394377720017 - 2² = 394377720013 is a prime.

Together with 394377720019, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (394377720013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197188860008 + 197188860009.

It is an arithmetic number, because the mean of its divisors is an integer number (197188860009).

Almost surely, 2^394377720017 is an apocalyptic number.

It is an amenable number.

394377720017 is a deficient number, since it is larger than the sum of its proper divisors (1).

394377720017 is an equidigital number, since it uses as much as digits as its factorization.

394377720017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1555848, while the sum is 50.

The spelling of 394377720017 in words is "three hundred ninety-four billion, three hundred seventy-seven million, seven hundred twenty thousand, seventeen".