13281986 has 4 divisors (see below), whose sum is σ = 19922982. Its totient is φ = 6640992.

The previous prime is 13281973. The next prime is 13282019. The reversal of 13281986 is 68918231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68918231 = 3533 ⋅19507.

It can be written as a sum of positive squares in only one way, i.e., 6682225 + 6599761 = 2585^2 + 2569^2 .

It is a super-2 number, since 2×13281986² = 352822304208392, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 3320495 + ... + 3320498.

Almost surely, 2^13281986 is an apocalyptic number.

13281986 is a deficient number, since it is larger than the sum of its proper divisors (6640996).

13281986 is an equidigital number, since it uses as much as digits as its factorization.

13281986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6640995.

The product of its digits is 20736, while the sum is 38.

The square root of 13281986 is about 3644.4459112463. The cubic root of 13281986 is about 236.8214337375.

The spelling of 13281986 in words is "thirteen million, two hundred eighty-one thousand, nine hundred eighty-six".