13805021 has 4 divisors (see below), whose sum is σ = 14126112. Its totient is φ = 13483932.

The previous prime is 13805009. The next prime is 13805041. The reversal of 13805021 is 12050831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 13805021 - 2¹⁴ = 13788637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13804984 and 13805002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13805041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160481 + ... + 160566.

It is an arithmetic number, because the mean of its divisors is an integer number (3531528).

Almost surely, 2^13805021 is an apocalyptic number.

It is an amenable number.

13805021 is a deficient number, since it is larger than the sum of its proper divisors (321091).

13805021 is an equidigital number, since it uses as much as digits as its factorization.

13805021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321090.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 13805021 is about 3715.5108666239. The cubic root of 13805021 is about 239.8901175228.

Adding to 13805021 its reverse (12050831), we get a palindrome (25855852).

The spelling of 13805021 in words is "thirteen million, eight hundred five thousand, twenty-one".