19778228 has 6 divisors (see below), whose sum is σ = 34611906. Its totient is φ = 9889112.

The previous prime is 19778219. The next prime is 19778233. The reversal of 19778228 is 82287791.

It can be written as a sum of positive squares in only one way, i.e., 17623204 + 2155024 = 4198^2 + 1468^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2472275 + ... + 2472282.

It is an arithmetic number, because the mean of its divisors is an integer number (5768651).

Almost surely, 2^19778228 is an apocalyptic number.

It is an amenable number.

19778228 is a deficient number, since it is larger than the sum of its proper divisors (14833678).

19778228 is a wasteful number, since it uses less digits than its factorization.

19778228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4944561 (or 4944559 counting only the distinct ones).

The product of its digits is 112896, while the sum is 44.

The square root of 19778228 is about 4447.2719727941. The cubic root of 19778228 is about 270.4347271961.

The spelling of 19778228 in words is "nineteen million, seven hundred seventy-eight thousand, two hundred twenty-eight".