643552113651 has 4 divisors (see below), whose sum is σ = 858069484872. Its totient is φ = 429034742432.

The previous prime is 643552113649. The next prime is 643552113691. The reversal of 643552113651 is 156311255346.

It is a happy number.

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 643552113651 - 2¹ = 643552113649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643552113601) 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, 107258685606 + ... + 107258685611.

It is an arithmetic number, because the mean of its divisors is an integer number (214517371218).

Almost surely, 2^643552113651 is an apocalyptic number.

643552113651 is a deficient number, since it is larger than the sum of its proper divisors (214517371221).

643552113651 is a wasteful number, since it uses less digits than its factorization.

643552113651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214517371220.

The product of its digits is 324000, while the sum is 42.

Adding to 643552113651 its reverse (156311255346), we get a palindrome (799863368997).

The spelling of 643552113651 in words is "six hundred forty-three billion, five hundred fifty-two million, one hundred thirteen thousand, six hundred fifty-one".