13642641281 has 4 divisors (see below), whose sum is σ = 13829526852. Its totient is φ = 13455755712.

The previous prime is 13642641263. The next prime is 13642641289. The reversal of 13642641281 is 18214624631.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10097034256 + 3545607025 = 100484^2 + 59545^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13642641281 is a prime.

It is a super-2 number, since 2×13642641281² (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 (13642641289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93442676 + ... + 93442821.

It is an arithmetic number, because the mean of its divisors is an integer number (3457381713).

Almost surely, 2^13642641281 is an apocalyptic number.

It is an amenable number.

13642641281 is a deficient number, since it is larger than the sum of its proper divisors (186885571).

13642641281 is an equidigital number, since it uses as much as digits as its factorization.

13642641281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186885570.

The product of its digits is 55296, while the sum is 38.

The spelling of 13642641281 in words is "thirteen billion, six hundred forty-two million, six hundred forty-one thousand, two hundred eighty-one".