18653216 has 36 divisors (see below), whose sum is σ = 39030138. Its totient is φ = 8773632.

The previous prime is 18653213. The next prime is 18653273. The reversal of 18653216 is 61235681.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 18490000 + 163216 = 4300^2 + 404^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (18653213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8240 + ... + 10256.

Almost surely, 2^18653216 is an apocalyptic number.

18653216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18653216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19515069).

18653216 is an abundant number, since it is smaller than the sum of its proper divisors (20376922).

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

18653216 is a wasteful number, since it uses less digits than its factorization.

18653216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2061 (or 2036 counting only the distinct ones).

The product of its digits is 8640, while the sum is 32.

The square root of 18653216 is about 4318.9369062305. The cubic root of 18653216 is about 265.2067497734.

Adding to 18653216 its reverse (61235681), we get a palindrome (79888897).

The spelling of 18653216 in words is "eighteen million, six hundred fifty-three thousand, two hundred sixteen".