20788068665 has 64 divisors (see below), whose sum is σ = 31596203520. Its totient is φ = 12778076160.

The previous prime is 20788068661. The next prime is 20788068667. The reversal of 20788068665 is 56686088702.

It is not a de Polignac number, because 20788068665 - 2² = 20788068661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20788068665.

It is not an unprimeable number, because it can be changed into a prime (20788068661) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4232231 + ... + 4237139.

It is an arithmetic number, because the mean of its divisors is an integer number (493690680).

Almost surely, 2^20788068665 is an apocalyptic number.

It is an amenable number.

20788068665 is a deficient number, since it is larger than the sum of its proper divisors (10808134855).

20788068665 is a wasteful number, since it uses less digits than its factorization.

20788068665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5202.

The product of its (nonzero) digits is 7741440, while the sum is 56.

The spelling of 20788068665 in words is "twenty billion, seven hundred eighty-eight million, sixty-eight thousand, six hundred sixty-five".