20428808 has 8 divisors (see below), whose sum is σ = 38304030. Its totient is φ = 10214400.

The previous prime is 20428801. The next prime is 20428817. The reversal of 20428808 is 80882402.

It can be written as a sum of positive squares in only one way, i.e., 16826404 + 3602404 = 4102^2 + 1898^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (20428801) by changing a digit.

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 as a sum of consecutive naturals, namely, 1276793 + ... + 1276808.

Almost surely, 2^20428808 is an apocalyptic number.

It is an amenable number.

20428808 is a deficient number, since it is larger than the sum of its proper divisors (17875222).

20428808 is a wasteful number, since it uses less digits than its factorization.

20428808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2553607 (or 2553603 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 32.

The square root of 20428808 is about 4519.8238903745. The cubic root of 20428808 is about 273.3680000977.

The spelling of 20428808 in words is "twenty million, four hundred twenty-eight thousand, eight hundred eight".