643430404131 has 12 divisors (see below), whose sum is σ = 879342133656. Its totient is φ = 418491316480.

The previous prime is 643430404129. The next prime is 643430404157. The reversal of 643430404131 is 131404034346.

It is a happy number.

It is not a de Polignac number, because 643430404131 - 2¹ = 643430404129 is a prime.

It is a super-2 number, since 2×643430404131² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643430404092 and 643430404101.

It is not an unprimeable number, because it can be changed into a prime (643430404181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63789366 + ... + 63799451.

It is an arithmetic number, because the mean of its divisors is an integer number (73278511138).

Almost surely, 2^643430404131 is an apocalyptic number.

643430404131 is a deficient number, since it is larger than the sum of its proper divisors (235911729525).

643430404131 is a wasteful number, since it uses less digits than its factorization.

643430404131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127588902 (or 127588861 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 33.

Adding to 643430404131 its reverse (131404034346), we get a palindrome (774834438477).

The spelling of 643430404131 in words is "six hundred forty-three billion, four hundred thirty million, four hundred four thousand, one hundred thirty-one".