20918016 has 108 divisors (see below), whose sum is σ = 68980912. Its totient is φ = 5971968.

The previous prime is 20918011. The next prime is 20918033. The reversal of 20918016 is 61081902.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20918011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15480 + ... + 16776.

Almost surely, 2^20918016 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 20918016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34490456).

20918016 is an abundant number, since it is smaller than the sum of its proper divisors (48062896).

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

20918016 is a wasteful number, since it uses less digits than its factorization.

20918016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1326 (or 1309 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 20918016 is about 4573.6217596124. The cubic root of 20918016 is about 275.5329214075.

Adding to 20918016 its reverse (61081902), we get a palindrome (81999918).

It can be divided in two parts, 209 and 18016, that added together give a square (18225 = 135²).

The spelling of 20918016 in words is "twenty million, nine hundred eighteen thousand, sixteen".