861868671 has 16 divisors (see below), whose sum is σ = 1221392640. Its totient is φ = 539049600.

The previous prime is 861868663. The next prime is 861868681. The reversal of 861868671 is 176868168.

It is not a de Polignac number, because 861868671 - 2³ = 861868663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861868681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67530 + ... + 79271.

It is an arithmetic number, because the mean of its divisors is an integer number (76337040).

Almost surely, 2^861868671 is an apocalyptic number.

861868671 is a deficient number, since it is larger than the sum of its proper divisors (359523969).

861868671 is a wasteful number, since it uses less digits than its factorization.

861868671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146926.

The product of its digits is 774144, while the sum is 51.

The square root of 861868671 is about 29357.5998848680. The cubic root of 861868671 is about 951.6568210682.

The spelling of 861868671 in words is "eight hundred sixty-one million, eight hundred sixty-eight thousand, six hundred seventy-one".