6636737585681 has 4 divisors (see below), whose sum is σ = 7584842955072. Its totient is φ = 5688632216292.

The previous prime is 6636737585669. The next prime is 6636737585711. The reversal of 6636737585681 is 1865857376366.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6636737585681 - 2²² = 6636733391377 is a prime.

It is a super-2 number, since 2×6636737585681² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6636737584681) 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 3 ways as a sum of consecutive naturals, for example, 474052684685 + ... + 474052684698.

It is an arithmetic number, because the mean of its divisors is an integer number (1896210738768).

Almost surely, 2^{6636737585681} is an apocalyptic number.

It is an amenable number.

6636737585681 is a deficient number, since it is larger than the sum of its proper divisors (948105369391).

6636737585681 is an equidigital number, since it uses as much as digits as its factorization.

6636737585681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 948105369390.

The product of its digits is 914457600, while the sum is 71.

The spelling of 6636737585681 in words is "six trillion, six hundred thirty-six billion, seven hundred thirty-seven million, five hundred eighty-five thousand, six hundred eighty-one".