20688071 has 2 divisors, whose sum is σ = 20688072. Its totient is φ = 20688070.

The previous prime is 20688043. The next prime is 20688077. The reversal of 20688071 is 17088602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20688071 - 2⁶ = 20688007 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20688077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10344035 + 10344036.

It is an arithmetic number, because the mean of its divisors is an integer number (10344036).

Almost surely, 2^20688071 is an apocalyptic number.

20688071 is a deficient number, since it is larger than the sum of its proper divisors (1).

20688071 is an equidigital number, since it uses as much as digits as its factorization.

20688071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 20688071 is about 4548.4141192288. The cubic root of 20688071 is about 274.5195843594.

The spelling of 20688071 in words is "twenty million, six hundred eighty-eight thousand, seventy-one".