13566421 has 8 divisors (see below), whose sum is σ = 14947488. Its totient is φ = 12210000.

The previous prime is 13566407. The next prime is 13566431. The reversal of 13566421 is 12466531.

13566421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 13566421 - 2¹⁷ = 13435349 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 13566421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13566431) 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, 4995 + ... + 7216.

It is an arithmetic number, because the mean of its divisors is an integer number (1868436).

Almost surely, 2^13566421 is an apocalyptic number.

13566421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13566421 is a deficient number, since it is larger than the sum of its proper divisors (1381067).

13566421 is a wasteful number, since it uses less digits than its factorization.

13566421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12323.

The product of its digits is 4320, while the sum is 28.

The square root of 13566421 is about 3683.2622768410. The cubic root of 13566421 is about 238.5000256378.

It can be divided in two parts, 1356 and 6421, that added together give a palindrome (7777).

The spelling of 13566421 in words is "thirteen million, five hundred sixty-six thousand, four hundred twenty-one".