13661643 has 8 divisors (see below), whose sum is σ = 18270928. Its totient is φ = 9080064.

The previous prime is 13661623. The next prime is 13661647. The reversal of 13661643 is 34616631.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 13661643 - 2¹² = 13657547 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13661643.

It is not an unprimeable number, because it can be changed into a prime (13661647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5746 + ... + 7767.

It is an arithmetic number, because the mean of its divisors is an integer number (2283866).

Almost surely, 2^13661643 is an apocalyptic number.

13661643 is a deficient number, since it is larger than the sum of its proper divisors (4609285).

13661643 is a wasteful number, since it uses less digits than its factorization.

13661643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13853.

The product of its digits is 7776, while the sum is 30.

The square root of 13661643 is about 3696.1659865325. The cubic root of 13661643 is about 239.0567315708.

The spelling of 13661643 in words is "thirteen million, six hundred sixty-one thousand, six hundred forty-three".