1605120017 has 2 divisors, whose sum is σ = 1605120018. Its totient is φ = 1605120016.

The previous prime is 1605120001. The next prime is 1605120037. The reversal of 1605120017 is 7100215061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1334879296 + 270240721 = 36536^2 + 16439^2 .

It is an emirp because it is prime and its reverse (7100215061) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1605120017 - 2⁴ = 1605120001 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1605119974 and 1605120001.

It is not a weakly prime, because it can be changed into another prime (1605120037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802560008 + 802560009.

It is an arithmetic number, because the mean of its divisors is an integer number (802560009).

Almost surely, 2^1605120017 is an apocalyptic number.

It is an amenable number.

1605120017 is a deficient number, since it is larger than the sum of its proper divisors (1).

1605120017 is an equidigital number, since it uses as much as digits as its factorization.

1605120017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 1605120017 is about 40063.9490939173. The cubic root of 1605120017 is about 1170.8533519281.

Adding to 1605120017 its reverse (7100215061), we get a palindrome (8705335078).

The spelling of 1605120017 in words is "one billion, six hundred five million, one hundred twenty thousand, seventeen".