18719228 has 24 divisors (see below), whose sum is σ = 35852544. Its totient is φ = 8481200.

The previous prime is 18719219. The next prime is 18719243. The reversal of 18719228 is 82291781.

It is a junction number, because it is equal to n+sod(n) for n = 18719191 and 18719200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20093 + ... + 21003.

It is an arithmetic number, because the mean of its divisors is an integer number (1493856).

Almost surely, 2^18719228 is an apocalyptic number.

It is an amenable number.

18719228 is a deficient number, since it is larger than the sum of its proper divisors (17133316).

18719228 is a wasteful number, since it uses less digits than its factorization.

18719228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1393 (or 1391 counting only the distinct ones).

The product of its digits is 16128, while the sum is 38.

The square root of 18719228 is about 4326.5723153554. The cubic root of 18719228 is about 265.5192288082.

The spelling of 18719228 in words is "eighteen million, seven hundred nineteen thousand, two hundred twenty-eight".