21113144 has 16 divisors (see below), whose sum is σ = 42632520. Its totient is φ = 9744480.

The previous prime is 21113119. The next prime is 21113153. The reversal of 21113144 is 44131112.

It is a happy number.

It is a Smith number, since the sum of its digits (17) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101402 + ... + 101609.

Almost surely, 2^21113144 is an apocalyptic number.

It is an amenable number.

21113144 is an abundant number, since it is smaller than the sum of its proper divisors (21519376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21113144 is a wasteful number, since it uses less digits than its factorization.

21113144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203030 (or 203026 counting only the distinct ones).

The product of its digits is 96, while the sum is 17.

The square root of 21113144 is about 4594.9041339292. The cubic root of 21113144 is about 276.3870156972.

Adding to 21113144 its reverse (44131112), we get a palindrome (65244256).

The spelling of 21113144 in words is "twenty-one million, one hundred thirteen thousand, one hundred forty-four".