1643235244 has 48 divisors (see below), whose sum is σ = 3376945152. Its totient is φ = 685040832.

The previous prime is 1643235211. The next prime is 1643235247. The reversal of 1643235244 is 4425323461.

It is not an unprimeable number, because it can be changed into a prime (1643235247) 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 15 ways as a sum of consecutive naturals, for example, 216034 + ... + 223510.

It is an arithmetic number, because the mean of its divisors is an integer number (70353024).

Almost surely, 2^1643235244 is an apocalyptic number.

1643235244 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 1643235244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1688472576).

1643235244 is an abundant number, since it is smaller than the sum of its proper divisors (1733709908).

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

1643235244 is a wasteful number, since it uses less digits than its factorization.

1643235244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7702 (or 7700 counting only the distinct ones).

The product of its digits is 69120, while the sum is 34.

The square root of 1643235244 is about 40536.8381105384. The cubic root of 1643235244 is about 1180.0486535526.

The spelling of 1643235244 in words is "one billion, six hundred forty-three million, two hundred thirty-five thousand, two hundred forty-four".