1605564644 has 12 divisors (see below), whose sum is σ = 2822117424. Its totient is φ = 799245384.

The previous prime is 1605564641. The next prime is 1605564673. The reversal of 1605564644 is 4464655061.

It is not an unprimeable number, because it can be changed into a prime (1605564641) 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 in 3 ways as a sum of consecutive naturals, for example, 883214 + ... + 885029.

It is an arithmetic number, because the mean of its divisors is an integer number (235176452).

Almost surely, 2^1605564644 is an apocalyptic number.

It is an amenable number.

1605564644 is a deficient number, since it is larger than the sum of its proper divisors (1216552780).

1605564644 is a wasteful number, since it uses less digits than its factorization.

1605564644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1768474 (or 1768472 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 41.

The square root of 1605564644 is about 40069.4976759130. The cubic root of 1605564644 is about 1170.9614528689.

The spelling of 1605564644 in words is "one billion, six hundred five million, five hundred sixty-four thousand, six hundred forty-four".