1643243008 has 80 divisors (see below), whose sum is σ = 3705633360. Its totient is φ = 721100800.

The previous prime is 1643243003. The next prime is 1643243011. The reversal of 1643243008 is 8003423461.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643243003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158298 + ... + 168358.

It is an arithmetic number, because the mean of its divisors is an integer number (46320417).

Almost surely, 2^1643243008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1643243008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1852816680).

1643243008 is an abundant number, since it is smaller than the sum of its proper divisors (2062390352).

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

1643243008 is a wasteful number, since it uses less digits than its factorization.

1643243008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10119 (or 10103 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 1643243008 is about 40536.9338751712. The cubic root of 1643243008 is about 1180.0505120578.

Adding to 1643243008 its reverse (8003423461), we get a palindrome (9646666469).

The spelling of 1643243008 in words is "one billion, six hundred forty-three million, two hundred forty-three thousand, eight".