21148 has 12 divisors (see below), whose sum is σ = 39312. Its totient is φ = 9920.

The previous prime is 21143. The next prime is 21149. The reversal of 21148 is 84112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143) 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, 88 + ... + 223.

It is an arithmetic number, because the mean of its divisors is an integer number (3276).

2²¹¹⁴⁸ is an apocalyptic number.

It is an amenable number.

21148 is a deficient number, since it is larger than the sum of its proper divisors (18164).

21148 is a wasteful number, since it uses less digits than its factorization.

21148 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332 (or 330 counting only the distinct ones).

The product of its digits is 64, while the sum is 16.

The square root of 21148 is about 145.4235194183. The cubic root of 21148 is about 27.6539029204.

Adding to 21148 its product of digits (64), we get a palindrome (21212).

It can be divided in two parts, 21 and 148, that added together give a square (169 = 13²).

The spelling of 21148 in words is "twenty-one thousand, one hundred forty-eight".