1605449664 has 336 divisors, whose sum is σ = 5735970240. Its totient is φ = 418037760.

The previous prime is 1605449639. The next prime is 1605449701. The reversal of 1605449664 is 4669445061.

It is a happy number.

1605449664 is a `hidden beast` number, since 16 + 0 + 544 + 96 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 5713204 + ... + 5713484.

It is an arithmetic number, because the mean of its divisors is an integer number (17071340).

Almost surely, 2^1605449664 is an apocalyptic number.

1605449664 is a gapful number since it is divisible by the number (14) 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 1605449664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2867985120).

1605449664 is an abundant number, since it is smaller than the sum of its proper divisors (4130520576).

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

1605449664 is a wasteful number, since it uses less digits than its factorization.

1605449664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The square root of 1605449664 is about 40068.0628930324. The cubic root of 1605449664 is about 1170.9335000108.

The spelling of 1605449664 in words is "one billion, six hundred five million, four hundred forty-nine thousand, six hundred sixty-four".