20688668695 has 4 divisors (see below), whose sum is σ = 24826402440. Its totient is φ = 16550934952.

The previous prime is 20688668669. The next prime is 20688668699. The reversal of 20688668695 is 59686688602.

It is a happy number.

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 20688668695 - 2¹⁵ = 20688635927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20688668699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2068866865 + ... + 2068866874.

It is an arithmetic number, because the mean of its divisors is an integer number (6206600610).

Almost surely, 2^20688668695 is an apocalyptic number.

20688668695 is a deficient number, since it is larger than the sum of its proper divisors (4137733745).

20688668695 is an equidigital number, since it uses as much as digits as its factorization.

20688668695 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4137733744.

The product of its (nonzero) digits is 59719680, while the sum is 64.

The spelling of 20688668695 in words is "twenty billion, six hundred eighty-eight million, six hundred sixty-eight thousand, six hundred ninety-five".