82781720570117 has 16 divisors (see below), whose sum is σ = 90678719324160. Its totient is φ = 75329456862000.

The previous prime is 82781720570099. The next prime is 82781720570119. The reversal of 82781720570117 is 71107502718728.

It is a cyclic number.

It is not a de Polignac number, because 82781720570117 - 2³⁶ = 82713001093381 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 (82781720570119) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 983885009 + ... + 983969142.

It is an arithmetic number, because the mean of its divisors is an integer number (5667419957760).

Almost surely, 2^{82781720570117} is an apocalyptic number.

It is an amenable number.

82781720570117 is a deficient number, since it is larger than the sum of its proper divisors (7896998754043).

82781720570117 is a wasteful number, since it uses less digits than its factorization.

82781720570117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1967854264.

The product of its (nonzero) digits is 3073280, while the sum is 56.

The spelling of 82781720570117 in words is "eighty-two trillion, seven hundred eighty-one billion, seven hundred twenty million, five hundred seventy thousand, one hundred seventeen".