1643963795 has 4 divisors (see below), whose sum is σ = 1972756560. Its totient is φ = 1315171032.

The previous prime is 1643963779. The next prime is 1643963837. The reversal of 1643963795 is 5973693461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1643963795 - 2⁴ = 1643963779 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 164396375 + ... + 164396384.

It is an arithmetic number, because the mean of its divisors is an integer number (493189140).

Almost surely, 2^1643963795 is an apocalyptic number.

1643963795 is a deficient number, since it is larger than the sum of its proper divisors (328792765).

1643963795 is an equidigital number, since it uses as much as digits as its factorization.

1643963795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328792764.

The product of its digits is 3674160, while the sum is 53.

The square root of 1643963795 is about 40545.8233977311. The cubic root of 1643963795 is about 1180.2230247317.

The spelling of 1643963795 in words is "one billion, six hundred forty-three million, nine hundred sixty-three thousand, seven hundred ninety-five".