1268408643 has 4 divisors (see below), whose sum is σ = 1691211528. Its totient is φ = 845605760.

The previous prime is 1268408639. The next prime is 1268408651. The reversal of 1268408643 is 3468048621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3468048621 = 3 ⋅1156016207.

It is a cyclic number.

It is not a de Polignac number, because 1268408643 - 2² = 1268408639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1268408595 and 1268408604.

It is not an unprimeable number, because it can be changed into a prime (1268408633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 211401438 + ... + 211401443.

It is an arithmetic number, because the mean of its divisors is an integer number (422802882).

Almost surely, 2^1268408643 is an apocalyptic number.

1268408643 is a deficient number, since it is larger than the sum of its proper divisors (422802885).

1268408643 is an equidigital number, since it uses as much as digits as its factorization.

1268408643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 422802884.

The product of its (nonzero) digits is 221184, while the sum is 42.

The square root of 1268408643 is about 35614.7250866829. The cubic root of 1268408643 is about 1082.4796257635.

The spelling of 1268408643 in words is "one billion, two hundred sixty-eight million, four hundred eight thousand, six hundred forty-three".