842787556887861 has 12 divisors (see below), whose sum is σ = 1311002866270188. Its totient is φ = 518638496546304.

The previous prime is 842787556887851. The next prime is 842787556887863. The reversal of 842787556887861 is 168788655787248.

842787556887861 is a `hidden beast` number, since 8 + 42 + 7 + 8 + 7 + 556 + 8 + 8 + 7 + 8 + 6 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 182874395887236 + 659913161000625 = 13523106^2 + 25688775^2 .

It is not a de Polignac number, because 842787556887861 - 2²⁵ = 842787523333429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842787556887863) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3601656225900 + ... + 3601656226133.

It is an arithmetic number, because the mean of its divisors is an integer number (109250238855849).

Almost surely, 2^{842787556887861} is an apocalyptic number.

It is an amenable number.

842787556887861 is a deficient number, since it is larger than the sum of its proper divisors (468215309382327).

842787556887861 is a wasteful number, since it uses less digits than its factorization.

842787556887861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7203312452052 (or 7203312452049 counting only the distinct ones).

The product of its digits is 80923852800, while the sum is 90.

The spelling of 842787556887861 in words is "eight hundred forty-two trillion, seven hundred eighty-seven billion, five hundred fifty-six million, eight hundred eighty-seven thousand, eight hundred sixty-one".