8161220108497 has 2 divisors, whose sum is σ = 8161220108498. Its totient is φ = 8161220108496.

The previous prime is 8161220108453. The next prime is 8161220108507. The reversal of 8161220108497 is 7948010221618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5848034629441 + 2313185479056 = 2418271^2 + 1520916^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8161220108497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8161220108497.

It is not a weakly prime, because it can be changed into another prime (8161220106497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4080610054248 + 4080610054249.

It is an arithmetic number, because the mean of its divisors is an integer number (4080610054249).

Almost surely, 2^{8161220108497} is an apocalyptic number.

It is an amenable number.

8161220108497 is a deficient number, since it is larger than the sum of its proper divisors (1).

8161220108497 is an equidigital number, since it uses as much as digits as its factorization.

8161220108497 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 387072, while the sum is 49.

The spelling of 8161220108497 in words is "eight trillion, one hundred sixty-one billion, two hundred twenty million, one hundred eight thousand, four hundred ninety-seven".