21342105 has 24 divisors (see below), whose sum is σ = 38188800. Its totient is φ = 11014560.

The previous prime is 21342071. The next prime is 21342119. The reversal of 21342105 is 50124312.

It is not a de Polignac number, because 21342105 - 2¹⁰ = 21341081 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6255 + ... + 9044.

It is an arithmetic number, because the mean of its divisors is an integer number (1591200).

Almost surely, 2^21342105 is an apocalyptic number.

It is an amenable number.

21342105 is a deficient number, since it is larger than the sum of its proper divisors (16846695).

21342105 is a wasteful number, since it uses less digits than its factorization.

21342105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15341 (or 15338 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21342105 is about 4619.7516166998. The cubic root of 21342105 is about 277.3825166190.

Adding to 21342105 its reverse (50124312), we get a palindrome (71466417).

The spelling of 21342105 in words is "twenty-one million, three hundred forty-two thousand, one hundred five".