13643181865 has 8 divisors (see below), whose sum is σ = 16814300040. Its totient is φ = 10619557632.

The previous prime is 13643181821. The next prime is 13643181901. The reversal of 13643181865 is 56818134631.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3472862761 + 10170319104 = 58931^2 + 100848^2 .

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 13643181865 - 2⁹ = 13643181353 is a prime.

It is a super-2 number, since 2×13643181865² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36873280 + ... + 36873649.

It is an arithmetic number, because the mean of its divisors is an integer number (2101787505).

Almost surely, 2^13643181865 is an apocalyptic number.

It is an amenable number.

13643181865 is a deficient number, since it is larger than the sum of its proper divisors (3171118175).

13643181865 is an equidigital number, since it uses as much as digits as its factorization.

13643181865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73746971.

The product of its digits is 414720, while the sum is 46.

The spelling of 13643181865 in words is "thirteen billion, six hundred forty-three million, one hundred eighty-one thousand, eight hundred sixty-five".