13645666681 has 8 divisors (see below), whose sum is σ = 13680598464. Its totient is φ = 13610760240.

The previous prime is 13645666679. The next prime is 13645666687. The reversal of 13645666681 is 18666654631.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13645666681 - 2¹ = 13645666679 is a prime.

It is a super-2 number, since 2×13645666681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13645666687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1523091 + ... + 1532023.

It is an arithmetic number, because the mean of its divisors is an integer number (1710074808).

Almost surely, 2^13645666681 is an apocalyptic number.

It is an amenable number.

13645666681 is a deficient number, since it is larger than the sum of its proper divisors (34931783).

13645666681 is an equidigital number, since it uses as much as digits as its factorization.

13645666681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12671.

The product of its digits is 3732480, while the sum is 52.

The spelling of 13645666681 in words is "thirteen billion, six hundred forty-five million, six hundred sixty-six thousand, six hundred eighty-one".