19818225 has 36 divisors (see below), whose sum is σ = 40570816. Its totient is φ = 9059040.

The previous prime is 19818217. The next prime is 19818247. The reversal of 19818225 is 52281891.

It is not a de Polignac number, because 19818225 - 2³ = 19818217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19818225.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4717 + ... + 7866.

Almost surely, 2^19818225 is an apocalyptic number.

19818225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19818225 is an abundant number, since it is smaller than the sum of its proper divisors (20752591).

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

19818225 is a wasteful number, since it uses less digits than its factorization.

19818225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12606 (or 12598 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 19818225 is about 4451.7665033108. The cubic root of 19818225 is about 270.6169021715.

The spelling of 19818225 in words is "nineteen million, eight hundred eighteen thousand, two hundred twenty-five".