21473143 has 4 divisors (see below), whose sum is σ = 21485520. Its totient is φ = 21460768.

The previous prime is 21473107. The next prime is 21473147. The reversal of 21473143 is 34137412.

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 21473143 - 2⁹ = 21472631 is a prime.

It is a super-2 number, since 2×21473143² = 922191740596898, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21473147) 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, 3058 + ... + 7231.

It is an arithmetic number, because the mean of its divisors is an integer number (5371380).

Almost surely, 2^21473143 is an apocalyptic number.

21473143 is a deficient number, since it is larger than the sum of its proper divisors (12377).

21473143 is a wasteful number, since it uses less digits than its factorization.

21473143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12376.

The product of its digits is 2016, while the sum is 25.

The square root of 21473143 is about 4633.9122779785. The cubic root of 21473143 is about 277.9490573114.

The spelling of 21473143 in words is "twenty-one million, four hundred seventy-three thousand, one hundred forty-three".