10421 has 4 divisors (see below), whose sum is σ = 11052. Its totient is φ = 9792.

The previous prime is 10399. The next prime is 10427. The reversal of 10421 is 12401.

10421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3025 + 7396 = 55^2 + 86^2 .

It is not a de Polignac number, because 10421 - 2⁶ = 10357 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10399 and 10408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 290 + ... + 323.

It is an arithmetic number, because the mean of its divisors is an integer number (2763).

2¹⁰⁴²¹ is an apocalyptic number.

It is an amenable number.

10421 is a deficient number, since it is larger than the sum of its proper divisors (631).

10421 is an equidigital number, since it uses as much as digits as its factorization.

10421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 630.

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 10421 is about 102.0832993197. The cubic root of 10421 is about 21.8425396108.

Adding to 10421 its reverse (12401), we get a palindrome (22822).

It can be divided in two parts, 104 and 21, that added together give a cube (125 = 5³).

The spelling of 10421 in words is "ten thousand, four hundred twenty-one", and thus it is an iban number.