105421 has 4 divisors (see below), whose sum is σ = 107712. Its totient is φ = 103132.

The previous prime is 105407. The next prime is 105437. The reversal of 105421 is 124501.

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 105421 - 2⁵ = 105389 is a prime.

It is a super-2 number, since 2×105421² = 22227174482, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1075 + ... + 1168.

It is an arithmetic number, because the mean of its divisors is an integer number (26928).

2¹⁰⁵⁴²¹ is an apocalyptic number.

It is an amenable number.

105421 is a deficient number, since it is larger than the sum of its proper divisors (2291).

105421 is an equidigital number, since it uses as much as digits as its factorization.

105421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2290.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 105421 is about 324.6860021621. The cubic root of 105421 is about 47.2399080749.

Adding to 105421 its reverse (124501), we get a palindrome (229922).

The spelling of 105421 in words is "one hundred five thousand, four hundred twenty-one".