20681008 has 10 divisors (see below), whose sum is σ = 40069484. Its totient is φ = 10340496.

The previous prime is 20680997. The next prime is 20681009. The reversal of 20681008 is 80018602.

It is not an unprimeable number, because it can be changed into a prime (20681009) 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, 646266 + ... + 646297.

Almost surely, 2^20681008 is an apocalyptic number.

It is an amenable number.

20681008 is a deficient number, since it is larger than the sum of its proper divisors (19388476).

20681008 is a wasteful number, since it uses less digits than its factorization.

20681008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1292571 (or 1292565 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 20681008 is about 4547.6376284836. The cubic root of 20681008 is about 274.4883400654.

The spelling of 20681008 in words is "twenty million, six hundred eighty-one thousand, eight".