5638396643 has 4 divisors (see below), whose sum is σ = 6150978168. Its totient is φ = 5125815120.

The previous prime is 5638396639. The next prime is 5638396651. The reversal of 5638396643 is 3466938365.

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 5638396643 - 2² = 5638396639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5638396633) 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, 256290746 + ... + 256290767.

It is an arithmetic number, because the mean of its divisors is an integer number (1537744542).

Almost surely, 2^5638396643 is an apocalyptic number.

5638396643 is a deficient number, since it is larger than the sum of its proper divisors (512581525).

5638396643 is a wasteful number, since it uses less digits than its factorization.

5638396643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512581524.

The product of its digits is 8398080, while the sum is 53.

The square root of 5638396643 is about 75089.2578402530. The cubic root of 5638396643 is about 1779.8573974679.

The spelling of 5638396643 in words is "five billion, six hundred thirty-eight million, three hundred ninety-six thousand, six hundred forty-three".