13661289 has 6 divisors (see below), whose sum is σ = 19732986. Its totient is φ = 9107520.

The previous prime is 13661281. The next prime is 13661303. The reversal of 13661289 is 98216631.

13661289 is a `hidden beast` number, since 1 + 36 + 612 + 8 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 7371225 + 6290064 = 2715^2 + 2508^2 .

It is not a de Polignac number, because 13661289 - 2³ = 13661281 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13661281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 758952 + ... + 758969.

It is an arithmetic number, because the mean of its divisors is an integer number (3288831).

Almost surely, 2^13661289 is an apocalyptic number.

It is an amenable number.

13661289 is a deficient number, since it is larger than the sum of its proper divisors (6071697).

13661289 is a wasteful number, since it uses less digits than its factorization.

13661289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1517927 (or 1517924 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 13661289 is about 3696.1180987625. The cubic root of 13661289 is about 239.0546667432.

It can be divided in two parts, 136 and 61289, that added together give a triangular number (61425 = T₃₅₀).

The spelling of 13661289 in words is "thirteen million, six hundred sixty-one thousand, two hundred eighty-nine".