21216614 has 8 divisors (see below), whose sum is σ = 32685168. Its totient is φ = 10321560.

The previous prime is 21216607. The next prime is 21216619. The reversal of 21216614 is 41661212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21216614.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216619) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143282 + ... + 143429.

It is an arithmetic number, because the mean of its divisors is an integer number (4085646).

Almost surely, 2^21216614 is an apocalyptic number.

21216614 is a deficient number, since it is larger than the sum of its proper divisors (11468554).

21216614 is a wasteful number, since it uses less digits than its factorization.

21216614 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286750.

The product of its digits is 576, while the sum is 23.

The square root of 21216614 is about 4606.1495850656. The cubic root of 21216614 is about 276.8377803104.

Adding to 21216614 its reverse (41661212), we get a palindrome (62877826).

The spelling of 21216614 in words is "twenty-one million, two hundred sixteen thousand, six hundred fourteen".