6421579989 has 12 divisors (see below), whose sum is σ = 9411241728. Its totient is φ = 3891866440.

The previous prime is 6421579979. The next prime is 6421579991. The reversal of 6421579989 is 9899751246.

It is not a de Polignac number, because 6421579989 - 2⁴ = 6421579973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421579979) 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 11 ways as a sum of consecutive naturals, for example, 8844789 + ... + 8845514.

It is an arithmetic number, because the mean of its divisors is an integer number (784270144).

Almost surely, 2^6421579989 is an apocalyptic number.

It is an amenable number.

6421579989 is a deficient number, since it is larger than the sum of its proper divisors (2989661739).

6421579989 is a wasteful number, since it uses less digits than its factorization.

6421579989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17690328 (or 17690317 counting only the distinct ones).

The product of its digits is 9797760, while the sum is 60.

The square root of 6421579989 is about 80134.7614272358. The cubic root of 6421579989 is about 1858.7199722925.

The spelling of 6421579989 in words is "six billion, four hundred twenty-one million, five hundred seventy-nine thousand, nine hundred eighty-nine".