20911216 has 20 divisors (see below), whose sum is σ = 41611672. Its totient is φ = 10172736.

The previous prime is 20911213. The next prime is 20911223. The reversal of 20911216 is 61211902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20911211) 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, 17070 + ... + 18253.

Almost surely, 2^20911216 is an apocalyptic number.

It is an amenable number.

20911216 is a deficient number, since it is larger than the sum of its proper divisors (20700456).

20911216 is a wasteful number, since it uses less digits than its factorization.

20911216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35368 (or 35362 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 20911216 is about 4572.8783058376. The cubic root of 20911216 is about 275.5030615501.

The spelling of 20911216 in words is "twenty million, nine hundred eleven thousand, two hundred sixteen".