1605661301 has 2 divisors, whose sum is σ = 1605661302. Its totient is φ = 1605661300.

The previous prime is 1605661297. The next prime is 1605661319. The reversal of 1605661301 is 1031665061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1100580625 + 505080676 = 33175^2 + 22474^2 .

It is a cyclic number.

It is not a de Polignac number, because 1605661301 - 2² = 1605661297 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1605661391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802830650 + 802830651.

It is an arithmetic number, because the mean of its divisors is an integer number (802830651).

Almost surely, 2^1605661301 is an apocalyptic number.

It is an amenable number.

1605661301 is a deficient number, since it is larger than the sum of its proper divisors (1).

1605661301 is an equidigital number, since it uses as much as digits as its factorization.

1605661301 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 1605661301 is about 40070.7037747030. The cubic root of 1605661301 is about 1170.9849501788.

The spelling of 1605661301 in words is "one billion, six hundred five million, six hundred sixty-one thousand, three hundred one".