13661538587 has 8 divisors (see below), whose sum is σ = 14127057936. Its totient is φ = 13203713952.

The previous prime is 13661538571. The next prime is 13661538607. The reversal of 13661538587 is 78583516631.

It is a happy number.

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 13661538587 - 2⁴ = 13661538571 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13661538287) 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, 1920068 + ... + 1927169.

It is an arithmetic number, because the mean of its divisors is an integer number (1765882242).

Almost surely, 2^13661538587 is an apocalyptic number.

13661538587 is a deficient number, since it is larger than the sum of its proper divisors (465519349).

13661538587 is an equidigital number, since it uses as much as digits as its factorization.

13661538587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3847357.

The product of its digits is 3628800, while the sum is 53.

The spelling of 13661538587 in words is "thirteen billion, six hundred sixty-one million, five hundred thirty-eight thousand, five hundred eighty-seven".