1234635643 has 4 divisors (see below), whose sum is σ = 1243647720. Its totient is φ = 1225623568.

The previous prime is 1234635631. The next prime is 1234635673. The reversal of 1234635643 is 3465364321.

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 1234635643 - 2⁹ = 1234635131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1234635673) 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, 4505833 + ... + 4506106.

It is an arithmetic number, because the mean of its divisors is an integer number (310911930).

Almost surely, 2^1234635643 is an apocalyptic number.

1234635643 is a deficient number, since it is larger than the sum of its proper divisors (9012077).

1234635643 is an equidigital number, since it uses as much as digits as its factorization.

1234635643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9012076.

The product of its digits is 155520, while the sum is 37.

The square root of 1234635643 is about 35137.3824153138. The cubic root of 1234635643 is about 1072.7856037229.

Adding to 1234635643 its reverse (3465364321), we get a palindrome (4699999964).

The spelling of 1234635643 in words is "one billion, two hundred thirty-four million, six hundred thirty-five thousand, six hundred forty-three".