19815222 has 16 divisors (see below), whose sum is σ = 45292032. Its totient is φ = 5661480.

The previous prime is 19815203. The next prime is 19815253. The reversal of 19815222 is 22251891.

It is a self number, because there is not a number n which added to its sum of digits gives 19815222.

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, 235854 + ... + 235937.

It is an arithmetic number, because the mean of its divisors is an integer number (2830752).

Almost surely, 2^19815222 is an apocalyptic number.

19815222 is an abundant number, since it is smaller than the sum of its proper divisors (25476810).

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

19815222 is a wasteful number, since it uses less digits than its factorization.

19815222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471803.

The product of its digits is 2880, while the sum is 30.

The square root of 19815222 is about 4451.4292086924. The cubic root of 19815222 is about 270.6032328746.

The spelling of 19815222 in words is "nineteen million, eight hundred fifteen thousand, two hundred twenty-two".