20681695 has 4 divisors (see below), whose sum is σ = 24818040. Its totient is φ = 16545352.

The previous prime is 20681663. The next prime is 20681701. The reversal of 20681695 is 59618602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20681695 - 2⁵ = 20681663 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2068165 + ... + 2068174.

It is an arithmetic number, because the mean of its divisors is an integer number (6204510).

Almost surely, 2^20681695 is an apocalyptic number.

20681695 is a deficient number, since it is larger than the sum of its proper divisors (4136345).

20681695 is an equidigital number, since it uses as much as digits as its factorization.

20681695 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4136344.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 20681695 is about 4547.7131615791. The cubic root of 20681695 is about 274.4913794305.

The spelling of 20681695 in words is "twenty million, six hundred eighty-one thousand, six hundred ninety-five".