20809410085 has 8 divisors (see below), whose sum is σ = 25832371320. Its totient is φ = 16073475264.

The previous prime is 20809410073. The next prime is 20809410091. The reversal of 20809410085 is 58001490802.

It can be written as a sum of positive squares in 4 ways, for example, as 4006510209 + 16802899876 = 63297^2 + 129626^2 .

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 20809410085 - 2⁹ = 20809409573 is a prime.

It is a super-3 number, since 3×20809410085³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71756442 + ... + 71756731.

It is an arithmetic number, because the mean of its divisors is an integer number (3229046415).

Almost surely, 2^20809410085 is an apocalyptic number.

It is an amenable number.

20809410085 is a deficient number, since it is larger than the sum of its proper divisors (5022961235).

20809410085 is a wasteful number, since it uses less digits than its factorization.

20809410085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143513207.

The product of its (nonzero) digits is 23040, while the sum is 37.

The spelling of 20809410085 in words is "twenty billion, eight hundred nine million, four hundred ten thousand, eighty-five".