13662981 has 6 divisors (see below), whose sum is σ = 19735430. Its totient is φ = 9108648.

The previous prime is 13662959. The next prime is 13662983. The reversal of 13662981 is 18926631.

13662981 is a `hidden beast` number, since 1 + 366 + 298 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11840481 + 1822500 = 3441^2 + 1350^2 .

It is not a de Polignac number, because 13662981 - 2⁹ = 13662469 is a prime.

It is a super-2 number, since 2×13662981² = 373354099612722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13662983) 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, 759046 + ... + 759063.

Almost surely, 2^13662981 is an apocalyptic number.

It is an amenable number.

13662981 is a deficient number, since it is larger than the sum of its proper divisors (6072449).

13662981 is a wasteful number, since it uses less digits than its factorization.

13662981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1518115 (or 1518112 counting only the distinct ones).

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

The square root of 13662981 is about 3696.3469804660. The cubic root of 13662981 is about 239.0645355972.

The spelling of 13662981 in words is "thirteen million, six hundred sixty-two thousand, nine hundred eighty-one".