861869217024 has 90 divisors (see below), whose sum is σ = 2569938119210. Its totient is φ = 287289732096.

The previous prime is 861869216987. The next prime is 861869217037. The reversal of 861869217024 is 420712968168.

It is a happy number.

861869217024 is a `hidden beast` number, since 8 + 618 + 6 + 9 + 2 + 17 + 0 + 2 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 861867143424 + 2073600 = 928368^2 + 1440^2 .

It is a super-2 number, since 2×861869217024² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 20761219 + ... + 20802690.

Almost surely, 2^861869217024 is an apocalyptic number.

It is an amenable number.

861869217024 is an abundant number, since it is smaller than the sum of its proper divisors (1708068902186).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861869217024 is an equidigital number, since it uses as much as digits as its factorization.

861869217024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41563937 (or 41563914 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The spelling of 861869217024 in words is "eight hundred sixty-one billion, eight hundred sixty-nine million, two hundred seventeen thousand, twenty-four".