6566634621 has 12 divisors (see below), whose sum is σ = 9507781920. Its totient is φ = 4367305800.

The previous prime is 6566634617. The next prime is 6566634649. The reversal of 6566634621 is 1264366656.

It is not a de Polignac number, because 6566634621 - 2² = 6566634617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6566634611) 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, 866905 + ... + 874446.

It is an arithmetic number, because the mean of its divisors is an integer number (792315160).

Almost surely, 2^6566634621 is an apocalyptic number.

It is an amenable number.

6566634621 is a deficient number, since it is larger than the sum of its proper divisors (2941147299).

6566634621 is a wasteful number, since it uses less digits than its factorization.

6566634621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1741776 (or 1741773 counting only the distinct ones).

The product of its digits is 933120, while the sum is 45.

The square root of 6566634621 is about 81034.7741466588. The cubic root of 6566634621 is about 1872.6112034530.

The spelling of 6566634621 in words is "six billion, five hundred sixty-six million, six hundred thirty-four thousand, six hundred twenty-one".