21458143 has 4 divisors (see below), whose sum is σ = 24523600. Its totient is φ = 18392688.

The previous prime is 21458141. The next prime is 21458189. The reversal of 21458143 is 34185412.

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

It is a cyclic number.

It is not a de Polignac number, because 21458143 - 2¹ = 21458141 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21458141) 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, 1532718 + ... + 1532731.

It is an arithmetic number, because the mean of its divisors is an integer number (6130900).

Almost surely, 2^21458143 is an apocalyptic number.

21458143 is a deficient number, since it is larger than the sum of its proper divisors (3065457).

21458143 is an equidigital number, since it uses as much as digits as its factorization.

21458143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3065456.

The product of its digits is 3840, while the sum is 28.

The square root of 21458143 is about 4632.2934924290. The cubic root of 21458143 is about 277.8843220739.

The spelling of 21458143 in words is "twenty-one million, four hundred fifty-eight thousand, one hundred forty-three".