18690216 has 16 divisors (see below), whose sum is σ = 46725600. Its totient is φ = 6230064.

The previous prime is 18690211. The next prime is 18690223. The reversal of 18690216 is 61209681.

It is not an unprimeable number, because it can be changed into a prime (18690211) 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, 389356 + ... + 389403.

It is an arithmetic number, because the mean of its divisors is an integer number (2920350).

Almost surely, 2^18690216 is an apocalyptic number.

It is an amenable number.

18690216 is an abundant number, since it is smaller than the sum of its proper divisors (28035384).

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

18690216 is a wasteful number, since it uses less digits than its factorization.

18690216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 778768 (or 778764 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 18690216 is about 4323.2182457054. The cubic root of 18690216 is about 265.3819862018.

Adding to 18690216 its reverse (61209681), we get a palindrome (79899897).

The spelling of 18690216 in words is "eighteen million, six hundred ninety thousand, two hundred sixteen".