1645803648 has 48 divisors (see below), whose sum is σ = 4735974750. Its totient is φ = 548600832.

The previous prime is 1645803641. The next prime is 1645803659. The reversal of 1645803648 is 8463085461.

1645803648 is a `hidden beast` number, since 1 + 6 + 4 + 580 + 3 + 64 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1222761024 + 423042624 = 34968^2 + 20568^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (1645803641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 713173 + ... + 715476.

Almost surely, 2^1645803648 is an apocalyptic number.

1645803648 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1645803648 is an abundant number, since it is smaller than the sum of its proper divisors (3090171102).

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

1645803648 is a wasteful number, since it uses less digits than its factorization.

1645803648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1428669 (or 1428654 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The square root of 1645803648 is about 40568.5056170424. The cubic root of 1645803648 is about 1180.6631453968.

The spelling of 1645803648 in words is "one billion, six hundred forty-five million, eight hundred three thousand, six hundred forty-eight".