1604561669 has 2 divisors, whose sum is σ = 1604561670. Its totient is φ = 1604561668.

The previous prime is 1604561639. The next prime is 1604561689. The reversal of 1604561669 is 9661654061.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 825872644 + 778689025 = 28738^2 + 27905^2 .

It is a cyclic number.

It is not a de Polignac number, because 1604561669 - 2¹² = 1604557573 is a prime.

It is a super-2 number, since 2×1604561669² = 5149236299248131122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1604561639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802280834 + 802280835.

It is an arithmetic number, because the mean of its divisors is an integer number (802280835).

Almost surely, 2^1604561669 is an apocalyptic number.

It is an amenable number.

1604561669 is a deficient number, since it is larger than the sum of its proper divisors (1).

1604561669 is an equidigital number, since it uses as much as digits as its factorization.

1604561669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 1604561669 is about 40056.9802780988. The cubic root of 1604561669 is about 1170.7175740345.

The spelling of 1604561669 in words is "one billion, six hundred four million, five hundred sixty-one thousand, six hundred sixty-nine".