20163728 has 30 divisors (see below), whose sum is σ = 42309234. Its totient is φ = 9305088.

The previous prime is 20163707. The next prime is 20163739. The reversal of 20163728 is 82736102.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 200704 + 19963024 = 448^2 + 4468^2 .

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20163728.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1025 + ... + 6432.

Almost surely, 2^20163728 is an apocalyptic number.

It is an amenable number.

20163728 is an abundant number, since it is smaller than the sum of its proper divisors (22145506).

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

20163728 is a wasteful number, since it uses less digits than its factorization.

20163728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7491 (or 7472 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 20163728 is about 4490.4039907340. The cubic root of 20163728 is about 272.1804598313.

The spelling of 20163728 in words is "twenty million, one hundred sixty-three thousand, seven hundred twenty-eight".