861880851 has 32 divisors (see below), whose sum is σ = 1393958720. Its totient is φ = 523107072.

The previous prime is 861880847. The next prime is 861880853. The reversal of 861880851 is 158088168.

It is a happy number.

861880851 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 861880851 - 2² = 861880847 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 861880797 and 861880806.

It is not an unprimeable number, because it can be changed into a prime (861880853) 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, 8805 + ... + 42441.

It is an arithmetic number, because the mean of its divisors is an integer number (43561210).

Almost surely, 2^861880851 is an apocalyptic number.

861880851 is a deficient number, since it is larger than the sum of its proper divisors (532077869).

861880851 is a wasteful number, since it uses less digits than its factorization.

861880851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33732 (or 33726 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 45.

The square root of 861880851 is about 29357.8073261611. The cubic root of 861880851 is about 951.6613040116.

The spelling of 861880851 in words is "eight hundred sixty-one million, eight hundred eighty thousand, eight hundred fifty-one".