20161216 has 28 divisors (see below), whose sum is σ = 40416480. Its totient is φ = 9977600.

The previous prime is 20161199. The next prime is 20161237. The reversal of 20161216 is 61216102.

It is a junction number, because it is equal to n+sod(n) for n = 20161193 and 20161202.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4905 + ... + 8023.

Almost surely, 2^20161216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20161216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20208240).

20161216 is an abundant number, since it is smaller than the sum of its proper divisors (20255264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20161216 is a wasteful number, since it uses less digits than its factorization.

20161216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3232 (or 3222 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 20161216 is about 4490.1242744494. The cubic root of 20161216 is about 272.1691566022.

Adding to 20161216 its reverse (61216102), we get a palindrome (81377318).

The spelling of 20161216 in words is "twenty million, one hundred sixty-one thousand, two hundred sixteen".