21342185 has 4 divisors (see below), whose sum is σ = 25610628. Its totient is φ = 17073744.

The previous prime is 21342179. The next prime is 21342193. The reversal of 21342185 is 58124312.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16999129 + 4343056 = 4123^2 + 2084^2 .

It is a cyclic number.

It is not a de Polignac number, because 21342185 - 2⁴ = 21342169 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2134214 + ... + 2134223.

It is an arithmetic number, because the mean of its divisors is an integer number (6402657).

Almost surely, 2^21342185 is an apocalyptic number.

It is an amenable number.

21342185 is a deficient number, since it is larger than the sum of its proper divisors (4268443).

21342185 is an equidigital number, since it uses as much as digits as its factorization.

21342185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4268442.

The product of its digits is 1920, while the sum is 26.

The square root of 21342185 is about 4619.7602751658. The cubic root of 21342185 is about 277.3828632042.

Adding to 21342185 its reverse (58124312), we get a palindrome (79466497).

The spelling of 21342185 in words is "twenty-one million, three hundred forty-two thousand, one hundred eighty-five".