13987181 has 8 divisors (see below), whose sum is σ = 15092280. Its totient is φ = 12886272.

The previous prime is 13987139. The next prime is 13987217. The reversal of 13987181 is 18178931.

It can be written as a sum of positive squares in 4 ways, for example, as 111556 + 13875625 = 334^2 + 3725^2 .

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 13987181 - 2¹⁰ = 13986157 is a prime.

It is a super-2 number, since 2×13987181² = 391282464653522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13987111) 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, 11825 + ... + 12953.

It is an arithmetic number, because the mean of its divisors is an integer number (1886535).

Almost surely, 2^13987181 is an apocalyptic number.

It is an amenable number.

13987181 is a deficient number, since it is larger than the sum of its proper divisors (1105099).

13987181 is a wasteful number, since it uses less digits than its factorization.

13987181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2095.

The product of its digits is 12096, while the sum is 38.

The square root of 13987181 is about 3739.9439835377. The cubic root of 13987181 is about 240.9406429693.

The spelling of 13987181 in words is "thirteen million, nine hundred eighty-seven thousand, one hundred eighty-one".