21024143 has 4 divisors (see below), whose sum is σ = 24027600. Its totient is φ = 18020688.

The previous prime is 21024137. The next prime is 21024173. The reversal of 21024143 is 34142012.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21024143 - 2⁸ = 21023887 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 (21024173) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1501718 + ... + 1501731.

It is an arithmetic number, because the mean of its divisors is an integer number (6006900).

Almost surely, 2^21024143 is an apocalyptic number.

21024143 is a deficient number, since it is larger than the sum of its proper divisors (3003457).

21024143 is an equidigital number, since it uses as much as digits as its factorization.

21024143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3003456.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21024143 is about 4585.2091555348. The cubic root of 21024143 is about 275.9981052520.

Adding to 21024143 its reverse (34142012), we get a palindrome (55166155).

The spelling of 21024143 in words is "twenty-one million, twenty-four thousand, one hundred forty-three".