20681107 has 2 divisors, whose sum is σ = 20681108. Its totient is φ = 20681106.

The previous prime is 20681083. The next prime is 20681137. The reversal of 20681107 is 70118602.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20681107 is a prime.

It is not a weakly prime, because it can be changed into another prime (20681137) by changing a digit.

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, 10340553 + 10340554.

It is an arithmetic number, because the mean of its divisors is an integer number (10340554).

Almost surely, 2^20681107 is an apocalyptic number.

20681107 is a deficient number, since it is larger than the sum of its proper divisors (1).

20681107 is an equidigital number, since it uses as much as digits as its factorization.

20681107 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 20681107 is about 4547.6485132429. The cubic root of 20681107 is about 274.4887780567.

Adding to 20681107 its reverse (70118602), we get a palindrome (90799709).

The spelling of 20681107 in words is "twenty million, six hundred eighty-one thousand, one hundred seven".