861415873 has 2 divisors, whose sum is σ = 861415874. Its totient is φ = 861415872.

The previous prime is 861415847. The next prime is 861415889. The reversal of 861415873 is 378514168.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 792309904 + 69105969 = 28148^2 + 8313^2 .

It is a cyclic number.

It is not a de Polignac number, because 861415873 - 2⁹ = 861415361 is a prime.

It is not a weakly prime, because it can be changed into another prime (861415813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430707936 + 430707937.

It is an arithmetic number, because the mean of its divisors is an integer number (430707937).

Almost surely, 2^861415873 is an apocalyptic number.

It is an amenable number.

861415873 is a deficient number, since it is larger than the sum of its proper divisors (1).

861415873 is an equidigital number, since it uses as much as digits as its factorization.

861415873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 43.

The square root of 861415873 is about 29349.8871037011. The cubic root of 861415873 is about 951.4901352751.

The spelling of 861415873 in words is "eight hundred sixty-one million, four hundred fifteen thousand, eight hundred seventy-three".