1643608512 has 168 divisors, whose sum is σ = 5798470496. Its totient is φ = 433465344.

The previous prime is 1643608511. The next prime is 1643608517. The reversal of 1643608512 is 2158063461.

It is a happy number.

1643608512 is a `hidden beast` number, since 1 + 6 + 43 + 608 + 5 + 1 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643608511) 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 23 ways as a sum of consecutive naturals, for example, 36738 + ... + 68094.

Almost surely, 2^1643608512 is an apocalyptic number.

1643608512 is a gapful number since it is divisible by the number (12) 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 1643608512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2899235248).

1643608512 is an abundant number, since it is smaller than the sum of its proper divisors (4154861984).

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

1643608512 is a wasteful number, since it uses less digits than its factorization.

1643608512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31395 (or 31382 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 1643608512 is about 40541.4419082499. The cubic root of 1643608512 is about 1180.1379978415.

The spelling of 1643608512 in words is "one billion, six hundred forty-three million, six hundred eight thousand, five hundred twelve".