21213143 has 8 divisors (see below), whose sum is σ = 24576288. Its totient is φ = 17933184.

The previous prime is 21213119. The next prime is 21213149. The reversal of 21213143 is 34131212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21213143 - 2⁸ = 21212887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213149) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20246 + ... + 21267.

It is an arithmetic number, because the mean of its divisors is an integer number (3072036).

Almost surely, 2^21213143 is an apocalyptic number.

21213143 is a deficient number, since it is larger than the sum of its proper divisors (3363145).

21213143 is an equidigital number, since it uses as much as digits as its factorization.

21213143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41593.

The product of its digits is 144, while the sum is 17.

The square root of 21213143 is about 4605.7727907486. The cubic root of 21213143 is about 276.8226827656.

Adding to 21213143 its reverse (34131212), we get a palindrome (55344355).

The spelling of 21213143 in words is "twenty-one million, two hundred thirteen thousand, one hundred forty-three".