13611631561205 has 4 divisors (see below), whose sum is σ = 16333957873452. Its totient is φ = 10889305248960.

The previous prime is 13611631561181. The next prime is 13611631561277. The reversal of 13611631561205 is 50216513611631.

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 2767268847121 + 10844362714084 = 1663511^2 + 3293078^2 .

It is not a de Polignac number, because 13611631561205 - 2⁸ = 13611631560949 is a prime.

It is a super-2 number, since 2×13611631561205² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1361163156116 + ... + 1361163156125.

It is an arithmetic number, because the mean of its divisors is an integer number (4083489468363).

Almost surely, 2^{13611631561205} is an apocalyptic number.

It is an amenable number.

13611631561205 is a deficient number, since it is larger than the sum of its proper divisors (2722326312247).

13611631561205 is an equidigital number, since it uses as much as digits as its factorization.

13611631561205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2722326312246.

The product of its (nonzero) digits is 97200, while the sum is 41.

The spelling of 13611631561205 in words is "thirteen trillion, six hundred eleven billion, six hundred thirty-one million, five hundred sixty-one thousand, two hundred five".