21143143 has 16 divisors (see below), whose sum is σ = 26033920. Its totient is φ = 16765056.

The previous prime is 21143137. The next prime is 21143179. The reversal of 21143143 is 34134112.

It is not a de Polignac number, because 21143143 - 2¹³ = 21134951 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a self number, because there is not a number n which added to its sum of digits gives 21143143.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3871 + ... + 7567.

It is an arithmetic number, because the mean of its divisors is an integer number (1627120).

Almost surely, 2^21143143 is an apocalyptic number.

21143143 is a deficient number, since it is larger than the sum of its proper divisors (4890777).

21143143 is a wasteful number, since it uses less digits than its factorization.

21143143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3766.

The product of its digits is 288, while the sum is 19.

The square root of 21143143 is about 4598.1673523264. The cubic root of 21143143 is about 276.5178569433.

Adding to 21143143 its reverse (34134112), we get a palindrome (55277255).

It can be divided in two parts, 21 and 143143, that multiplied together give a palindrome (3006003).

The spelling of 21143143 in words is "twenty-one million, one hundred forty-three thousand, one hundred forty-three".