13818421 has 4 divisors (see below), whose sum is σ = 13984992. Its totient is φ = 13651852.

The previous prime is 13818401. The next prime is 13818439. The reversal of 13818421 is 12481831.

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 a de Polignac number, because none of the positive numbers 2^k-13818421 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 13818421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13818401) 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 3 ways as a sum of consecutive naturals, for example, 83161 + ... + 83326.

It is an arithmetic number, because the mean of its divisors is an integer number (3496248).

Almost surely, 2^13818421 is an apocalyptic number.

It is an amenable number.

13818421 is a deficient number, since it is larger than the sum of its proper divisors (166571).

13818421 is an equidigital number, since it uses as much as digits as its factorization.

13818421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166570.

The product of its digits is 1536, while the sum is 28.

The square root of 13818421 is about 3717.3136806032. The cubic root of 13818421 is about 239.9677097762.

The spelling of 13818421 in words is "thirteen million, eight hundred eighteen thousand, four hundred twenty-one".