18919225 has 24 divisors (see below), whose sum is σ = 26373312. Its totient is φ = 13358400.

The previous prime is 18919213. The next prime is 18919237. The reversal of 18919225 is 52291981.

It is an interprime number because it is at equal distance from previous prime (18919213) and next prime (18919237).

It is not a de Polignac number, because 18919225 - 2¹¹ = 18917177 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6210 + ... + 8740.

It is an arithmetic number, because the mean of its divisors is an integer number (1098888).

Almost surely, 2^18919225 is an apocalyptic number.

It is an amenable number.

18919225 is a deficient number, since it is larger than the sum of its proper divisors (7454087).

18919225 is a wasteful number, since it uses less digits than its factorization.

18919225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2577 (or 2572 counting only the distinct ones).

The product of its digits is 12960, while the sum is 37.

The square root of 18919225 is about 4349.6235469291. The cubic root of 18919225 is about 266.4614871359.

The spelling of 18919225 in words is "eighteen million, nine hundred nineteen thousand, two hundred twenty-five".