21345143 has 8 divisors (see below), whose sum is σ = 22239360. Its totient is φ = 20463840.

The previous prime is 21345119. The next prime is 21345187. The reversal of 21345143 is 34154312.

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 21345143 - 2¹⁰ = 21344119 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 (21342143) 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, 221 + ... + 6537.

It is an arithmetic number, because the mean of its divisors is an integer number (2779920).

Almost surely, 2^21345143 is an apocalyptic number.

21345143 is a deficient number, since it is larger than the sum of its proper divisors (894217).

21345143 is a wasteful number, since it uses less digits than its factorization.

21345143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6457.

The product of its digits is 1440, while the sum is 23.

The square root of 21345143 is about 4620.0804105556. The cubic root of 21345143 is about 277.3956775842.

Adding to 21345143 its reverse (34154312), we get a palindrome (55499455).

The spelling of 21345143 in words is "twenty-one million, three hundred forty-five thousand, one hundred forty-three".