19018221 has 32 divisors (see below), whose sum is σ = 28262400. Its totient is φ = 11327040.

The previous prime is 19018201. The next prime is 19018243. The reversal of 19018221 is 12281091.

It is not a de Polignac number, because 19018221 - 2⁷ = 19018093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19018191 and 19018200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19018201) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82935 + ... + 83163.

It is an arithmetic number, because the mean of its divisors is an integer number (883200).

Almost surely, 2^19018221 is an apocalyptic number.

It is an amenable number.

19018221 is a deficient number, since it is larger than the sum of its proper divisors (9244179).

19018221 is a wasteful number, since it uses less digits than its factorization.

19018221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329.

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 19018221 is about 4360.9885347247. The cubic root of 19018221 is about 266.9254375252.

The spelling of 19018221 in words is "nineteen million, eighteen thousand, two hundred twenty-one".