21032218 has 8 divisors (see below), whose sum is σ = 32219712. Its totient is φ = 10292316.

The previous prime is 21032201. The next prime is 21032237. The reversal of 21032218 is 81223012.

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

It is a junction number, because it is equal to n+sod(n) for n = 21032195 and 21032204.

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, 111780 + ... + 111967.

It is an arithmetic number, because the mean of its divisors is an integer number (4027464).

Almost surely, 2^21032218 is an apocalyptic number.

21032218 is a deficient number, since it is larger than the sum of its proper divisors (11187494).

21032218 is a wasteful number, since it uses less digits than its factorization.

21032218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223796.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 21032218 is about 4586.0896197087. The cubic root of 21032218 is about 276.0334360528.

The spelling of 21032218 in words is "twenty-one million, thirty-two thousand, two hundred eighteen".