861842668321 has 8 divisors (see below), whose sum is σ = 865631701800. Its totient is φ = 858058510848.

The previous prime is 861842668273. The next prime is 861842668373. The reversal of 861842668321 is 123866248168.

861842668321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 85082472721 + 776760195600 = 291689^2 + 881340^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 861842668321 - 2²⁵ = 861809113889 is a prime.

It is a super-2 number, since 2×861842668321² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861842608321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 864496 + ... + 1571953.

It is an arithmetic number, because the mean of its divisors is an integer number (108203962725).

Almost surely, 2^861842668321 is an apocalyptic number.

It is an amenable number.

861842668321 is a deficient number, since it is larger than the sum of its proper divisors (3789033479).

861842668321 is a wasteful number, since it uses less digits than its factorization.

861842668321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2438003.

The product of its digits is 5308416, while the sum is 55.

The spelling of 861842668321 in words is "eight hundred sixty-one billion, eight hundred forty-two million, six hundred sixty-eight thousand, three hundred twenty-one".