20858055715117 has 4 divisors (see below), whose sum is σ = 21049414024540. Its totient is φ = 20666697405696.

The previous prime is 20858055715111. The next prime is 20858055715129. The reversal of 20858055715117 is 71151755085802.

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

It can be written as a sum of positive squares in 2 ways, for example, as 19049087204676 + 1808968510441 = 4364526^2 + 1344979^2 .

It is a cyclic number.

It is not a de Polignac number, because 20858055715117 - 2¹⁵ = 20858055682349 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 (20858055715111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95679154548 + ... + 95679154765.

It is an arithmetic number, because the mean of its divisors is an integer number (5262353506135).

Almost surely, 2^{20858055715117} is an apocalyptic number.

It is an amenable number.

20858055715117 is a deficient number, since it is larger than the sum of its proper divisors (191358309423).

20858055715117 is a wasteful number, since it uses less digits than its factorization.

20858055715117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191358309422.

The product of its (nonzero) digits is 3920000, while the sum is 55.

The spelling of 20858055715117 in words is "twenty trillion, eight hundred fifty-eight billion, fifty-five million, seven hundred fifteen thousand, one hundred seventeen".