1605242561 has 16 divisors (see below), whose sum is σ = 1832834304. Its totient is φ = 1392754944.

The previous prime is 1605242557. The next prime is 1605242579. The reversal of 1605242561 is 1652425061.

It is a cyclic number.

It is not a de Polignac number, because 1605242561 - 2² = 1605242557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1605242461) 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 in 15 ways as a sum of consecutive naturals, for example, 178376 + ... + 187158.

It is an arithmetic number, because the mean of its divisors is an integer number (114552144).

Almost surely, 2^1605242561 is an apocalyptic number.

It is an amenable number.

1605242561 is a deficient number, since it is larger than the sum of its proper divisors (227591743).

1605242561 is a wasteful number, since it uses less digits than its factorization.

1605242561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9640.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 1605242561 is about 40065.4784197069. The cubic root of 1605242561 is about 1170.8831477067.

The spelling of 1605242561 in words is "one billion, six hundred five million, two hundred forty-two thousand, five hundred sixty-one".