18837216 has 36 divisors (see below), whose sum is σ = 53569152. Its totient is φ = 6278976.

The previous prime is 18837209. The next prime is 18837233. The reversal of 18837216 is 61273881.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 32416 + ... + 32991.

It is an arithmetic number, because the mean of its divisors is an integer number (1488032).

Almost surely, 2^18837216 is an apocalyptic number.

18837216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18837216 is an abundant number, since it is smaller than the sum of its proper divisors (34731936).

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

18837216 is a wasteful number, since it uses less digits than its factorization.

18837216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65423 (or 65412 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 18837216 is about 4340.1861711222. The cubic root of 18837216 is about 266.0759200633.

The spelling of 18837216 in words is "eighteen million, eight hundred thirty-seven thousand, two hundred sixteen".