20115656717 has 8 divisors (see below), whose sum is σ = 21743550360. Its totient is φ = 18499268160.

The previous prime is 20115656713. The next prime is 20115656723. The reversal of 20115656717 is 71765651102.

It can be written as a sum of positive squares in 4 ways, for example, as 1396217956 + 18719438761 = 37366^2 + 136819^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20115656717 - 2² = 20115656713 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20115656711) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2872634 + ... + 2879627.

It is an arithmetic number, because the mean of its divisors is an integer number (2717943795).

Almost surely, 2^20115656717 is an apocalyptic number.

It is an amenable number.

20115656717 is a deficient number, since it is larger than the sum of its proper divisors (1627893643).

20115656717 is a wasteful number, since it uses less digits than its factorization.

20115656717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5752543.

The product of its (nonzero) digits is 88200, while the sum is 41.

The spelling of 20115656717 in words is "twenty billion, one hundred fifteen million, six hundred fifty-six thousand, seven hundred seventeen".