19990218 has 32 divisors (see below), whose sum is σ = 40896576. Its totient is φ = 6512768.

The previous prime is 19990213. The next prime is 19990241. The reversal of 19990218 is 81209991.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (19990213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68080 + ... + 68372.

It is an arithmetic number, because the mean of its divisors is an integer number (1278018).

Almost surely, 2^19990218 is an apocalyptic number.

19990218 is an abundant number, since it is smaller than the sum of its proper divisors (20906358).

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

19990218 is a wasteful number, since it uses less digits than its factorization.

19990218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518.

The product of its (nonzero) digits is 11664, while the sum is 39.

The square root of 19990218 is about 4471.0421603917. The cubic root of 19990218 is about 271.3975003874.

The spelling of 19990218 in words is "nineteen million, nine hundred ninety thousand, two hundred eighteen".