1643235049 has 4 divisors (see below), whose sum is σ = 1655778960. Its totient is φ = 1630691140.

The previous prime is 1643235031. The next prime is 1643235089. The reversal of 1643235049 is 9405323461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1643235049 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1643234999 and 1643235017.

It is not an unprimeable number, because it can be changed into a prime (1643235029) 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 3 ways as a sum of consecutive naturals, for example, 6271759 + ... + 6272020.

It is an arithmetic number, because the mean of its divisors is an integer number (413944740).

Almost surely, 2^1643235049 is an apocalyptic number.

It is an amenable number.

1643235049 is a deficient number, since it is larger than the sum of its proper divisors (12543911).

1643235049 is a wasteful number, since it uses less digits than its factorization.

1643235049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12543910.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 1643235049 is about 40536.8357053187. The cubic root of 1643235049 is about 1180.0486068745.

The spelling of 1643235049 in words is "one billion, six hundred forty-three million, two hundred thirty-five thousand, forty-nine".