11421 has 12 divisors (see below), whose sum is σ = 17472. Its totient is φ = 7452.

The previous prime is 11411. The next prime is 11423. The reversal of 11421 is 12411.

It is a happy number.

It is not a de Polignac number, because 11421 - 2⁹ = 10909 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11423) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 220 + ... + 266.

It is an arithmetic number, because the mean of its divisors is an integer number (1456).

2¹¹⁴²¹ is an apocalyptic number.

It is an amenable number.

11421 is a deficient number, since it is larger than the sum of its proper divisors (6051).

11421 is an frugal number, since it uses more digits than its factorization.

11421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62 (or 50 counting only the distinct ones).

The product of its digits is 8, while the sum is 9.

The square root of 11421 is about 106.8690787833. The cubic root of 11421 is about 22.5199822485.

Adding to 11421 its reverse (12411), we get a palindrome (23832).

Subtracting 11421 from its reverse (12411), we obtain a triangular number (990 = T₄₄).

The spelling of 11421 in words is "eleven thousand, four hundred twenty-one", and thus it is an iban number.