20281608 has 48 divisors (see below), whose sum is σ = 55493100. Its totient is φ = 6691200.

The previous prime is 20281603. The next prime is 20281609. The reversal of 20281608 is 80618202.

It can be written as a sum of positive squares in 2 ways, for example, as 17791524 + 2490084 = 4218^2 + 1578^2 .

It is a super-2 number, since 2×20281608² = 822687246131328, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20281603) 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 in 11 ways as a sum of consecutive naturals, for example, 5878 + ... + 8666.

Almost surely, 2^20281608 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20281608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27746550).

20281608 is an abundant number, since it is smaller than the sum of its proper divisors (35211492).

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

20281608 is a wasteful number, since it uses less digits than its factorization.

20281608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2902 (or 2895 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 20281608 is about 4503.5106306081. The cubic root of 20281608 is about 272.7098313695.

It can be divided in two parts, 202 and 81608, that added together give a triangular number (81810 = T₄₀₄).

The spelling of 20281608 in words is "twenty million, two hundred eighty-one thousand, six hundred eight".