827823781917 has 32 divisors (see below), whose sum is σ = 1338110991360. Its totient is φ = 501631144560.

The previous prime is 827823781903. The next prime is 827823781919. The reversal of 827823781917 is 719187328728.

827823781917 is a `hidden beast` number, since 8 + 2 + 78 + 2 + 378 + 191 + 7 = 666.

It is not a de Polignac number, because 827823781917 - 2⁴ = 827823781901 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (827823781919) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1664158 + ... + 2103584.

It is an arithmetic number, because the mean of its divisors is an integer number (41815968480).

Almost surely, 2^827823781917 is an apocalyptic number.

It is an amenable number.

827823781917 is a deficient number, since it is larger than the sum of its proper divisors (510287209443).

827823781917 is a wasteful number, since it uses less digits than its factorization.

827823781917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445790 (or 445784 counting only the distinct ones).

The product of its digits is 18966528, while the sum is 63.

The spelling of 827823781917 in words is "eight hundred twenty-seven billion, eight hundred twenty-three million, seven hundred eighty-one thousand, nine hundred seventeen".