1605536640 has 160 divisors (see below), whose sum is σ = 5733846360. Its totient is φ = 428129280.

The previous prime is 1605536609. The next prime is 1605536677. The reversal of 1605536640 is 466355061.

1605536640 is a `hidden beast` number, since 1 + 6 + 0 + 5 + 5 + 3 + 6 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1605536595 and 1605536604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 36355 + ... + 67325.

Almost surely, 2^1605536640 is an apocalyptic number.

1605536640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1605536640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2866923180).

1605536640 is an abundant number, since it is smaller than the sum of its proper divisors (4128309720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1605536640 is an equidigital number, since it uses as much as digits as its factorization.

1605536640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31002 (or 30981 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 1605536640 is about 40069.1482315260. The cubic root of 1605536640 is about 1170.9546449223.

The spelling of 1605536640 in words is "one billion, six hundred five million, five hundred thirty-six thousand, six hundred forty".