21214366 has 4 divisors (see below), whose sum is σ = 31821552. Its totient is φ = 10607182.

The previous prime is 21214327. The next prime is 21214373. The reversal of 21214366 is 66341212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21214366.

It is a congruent 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 as a sum of consecutive naturals, namely, 5303590 + ... + 5303593.

It is an arithmetic number, because the mean of its divisors is an integer number (7955388).

Almost surely, 2^21214366 is an apocalyptic number.

21214366 is a deficient number, since it is larger than the sum of its proper divisors (10607186).

21214366 is a wasteful number, since it uses less digits than its factorization.

21214366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10607185.

The product of its digits is 1728, while the sum is 25.

The square root of 21214366 is about 4605.9055569996. The cubic root of 21214366 is about 276.8280025436.

Adding to 21214366 its reverse (66341212), we get a palindrome (87555578).

The spelling of 21214366 in words is "twenty-one million, two hundred fourteen thousand, three hundred sixty-six".