1605104161 has 2 divisors, whose sum is σ = 1605104162. Its totient is φ = 1605104160.

The previous prime is 1605104159. The next prime is 1605104177. The reversal of 1605104161 is 1614015061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1187147025 + 417957136 = 34455^2 + 20444^2 .

It is a cyclic number.

It is not a de Polignac number, because 1605104161 - 2¹ = 1605104159 is a prime.

Together with 1605104159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1605104131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802552080 + 802552081.

It is an arithmetic number, because the mean of its divisors is an integer number (802552081).

Almost surely, 2^1605104161 is an apocalyptic number.

It is an amenable number.

1605104161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1605104161 is an equidigital number, since it uses as much as digits as its factorization.

1605104161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 1605104161 is about 40063.7512097906. The cubic root of 1605104161 is about 1170.8494965338.

The spelling of 1605104161 in words is "one billion, six hundred five million, one hundred four thousand, one hundred sixty-one".