861457187 has 2 divisors, whose sum is σ = 861457188. Its totient is φ = 861457186.

The previous prime is 861457183. The next prime is 861457213. The reversal of 861457187 is 781754168.

861457187 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 861457187 - 2² = 861457183 is a prime.

It is not a weakly prime, because it can be changed into another prime (861457183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430728593 + 430728594.

It is an arithmetic number, because the mean of its divisors is an integer number (430728594).

Almost surely, 2^861457187 is an apocalyptic number.

861457187 is a deficient number, since it is larger than the sum of its proper divisors (1).

861457187 is an equidigital number, since it uses as much as digits as its factorization.

861457187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 376320, while the sum is 47.

The square root of 861457187 is about 29350.5909139833. The cubic root of 861457187 is about 951.5053463697.

The spelling of 861457187 in words is "eight hundred sixty-one million, four hundred fifty-seven thousand, one hundred eighty-seven".