6421516611 has 24 divisors (see below), whose sum is σ = 8984846160. Its totient is φ = 4076528832.

The previous prime is 6421516601. The next prime is 6421516643. The reversal of 6421516611 is 1166151246.

It is not a de Polignac number, because 6421516611 - 2⁶ = 6421516547 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6421516601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 232105 + ... + 258293.

It is an arithmetic number, because the mean of its divisors is an integer number (374368590).

Almost surely, 2^6421516611 is an apocalyptic number.

6421516611 is a deficient number, since it is larger than the sum of its proper divisors (2563329549).

6421516611 is a wasteful number, since it uses less digits than its factorization.

6421516611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26323 (or 26276 counting only the distinct ones).

The product of its digits is 8640, while the sum is 33.

The square root of 6421516611 is about 80134.3659798965. The cubic root of 6421516611 is about 1858.7138573726.

Adding to 6421516611 its reverse (1166151246), we get a palindrome (7587667857).

The spelling of 6421516611 in words is "six billion, four hundred twenty-one million, five hundred sixteen thousand, six hundred eleven".