21342811 has 8 divisors (see below), whose sum is σ = 25233120. Its totient is φ = 17662848.

The previous prime is 21342809. The next prime is 21342817. The reversal of 21342811 is 11824312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21342811 - 2¹ = 21342809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21342817) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 52366 + ... + 52771.

It is an arithmetic number, because the mean of its divisors is an integer number (3154140).

Almost surely, 2^21342811 is an apocalyptic number.

21342811 is a deficient number, since it is larger than the sum of its proper divisors (3890309).

21342811 is a wasteful number, since it uses less digits than its factorization.

21342811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105173.

The product of its digits is 384, while the sum is 22.

The square root of 21342811 is about 4619.8280271023. The cubic root of 21342811 is about 277.3855752035.

The spelling of 21342811 in words is "twenty-one million, three hundred forty-two thousand, eight hundred eleven".