86878449781321 has 81 divisors (see below), whose sum is σ = 100759215378549. Its totient is φ = 74850242174400.

The previous prime is 86878449781297. The next prime is 86878449781399. The reversal of 86878449781321 is 12318794487868.

The square root of 86878449781321 is 9320861.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 26067774246921 + 60810675534400 = 5105661^2 + 7798120^2 .

It is not a de Polignac number, because 86878449781321 - 2⁵ = 86878449781289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (86878449761321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 181374633960 + ... + 181374634438.

Almost surely, 2^{86878449781321} is an apocalyptic number.

86878449781321 is the 9320861-st square number.

86878449781321 is the 4660431-st centered octagonal number.

It is an amenable number.

86878449781321 is a deficient number, since it is larger than the sum of its proper divisors (13880765597228).

86878449781321 is an frugal number, since it uses more digits than its factorization.

86878449781321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1160 (or 580 counting only the distinct ones).

The product of its digits is 1040449536, while the sum is 76.

The spelling of 86878449781321 in words is "eighty-six trillion, eight hundred seventy-eight billion, four hundred forty-nine million, seven hundred eighty-one thousand, three hundred twenty-one".