21095218 has 8 divisors (see below), whose sum is σ = 32115312. Its totient is φ = 10390116.

The previous prime is 21095201. The next prime is 21095227. The reversal of 21095218 is 81259012.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78580 + ... + 78847.

It is an arithmetic number, because the mean of its divisors is an integer number (4014414).

Almost surely, 2^21095218 is an apocalyptic number.

21095218 is a deficient number, since it is larger than the sum of its proper divisors (11020094).

21095218 is a wasteful number, since it uses less digits than its factorization.

21095218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157496.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 21095218 is about 4592.9530805354. The cubic root of 21095218 is about 276.3087719184.

The spelling of 21095218 in words is "twenty-one million, ninety-five thousand, two hundred eighteen".