13803561 has 8 divisors (see below), whose sum is σ = 20449760. Its totient is φ = 9202356.

The previous prime is 13803547. The next prime is 13803577. The reversal of 13803561 is 16530831.

It is not a de Polignac number, because 13803561 - 2¹⁴ = 13787177 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 511243 = 13803561 / (1 + 3 + 8 + 0 + 3 + 5 + 6 + 1).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13803661) 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, 255595 + ... + 255648.

It is an arithmetic number, because the mean of its divisors is an integer number (2556220).

Almost surely, 2^13803561 is an apocalyptic number.

It is an amenable number.

13803561 is a deficient number, since it is larger than the sum of its proper divisors (6646199).

13803561 is an equidigital number, since it uses as much as digits as its factorization.

13803561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511252 (or 511246 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 13803561 is about 3715.3143877739. The cubic root of 13803561 is about 239.8816604085.

The spelling of 13803561 in words is "thirteen million, eight hundred three thousand, five hundred sixty-one".