861782173321 has 8 divisors (see below), whose sum is σ = 873569440224. Its totient is φ = 850064040480.

The previous prime is 861782173309. The next prime is 861782173331. The reversal of 861782173321 is 123371287168.

It is a happy number.

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 861782173321 - 2¹¹ = 861782171273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861782173331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17258415 + ... + 17308276.

It is an arithmetic number, because the mean of its divisors is an integer number (109196180028).

Almost surely, 2^861782173321 is an apocalyptic number.

It is an amenable number.

861782173321 is a deficient number, since it is larger than the sum of its proper divisors (11787266903).

861782173321 is a wasteful number, since it uses less digits than its factorization.

861782173321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34567031.

The product of its digits is 677376, while the sum is 49.

The spelling of 861782173321 in words is "eight hundred sixty-one billion, seven hundred eighty-two million, one hundred seventy-three thousand, three hundred twenty-one".