81324408121280 has 112 divisors (see below), whose sum is σ = 202387753419264. Its totient is φ = 31067032888320.

The previous prime is 81324408121279. The next prime is 81324408121309. The reversal of 81324408121280 is 8212180442318.

It is a super-2 number, since 2×81324408121280² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 3859676 + ... + 13324635.

It is an arithmetic number, because the mean of its divisors is an integer number (1807033512672).

Almost surely, 2^{81324408121280} is an apocalyptic number.

81324408121280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81324408121280 is an abundant number, since it is smaller than the sum of its proper divisors (121063345297984).

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

81324408121280 is a wasteful number, since it uses less digits than its factorization.

81324408121280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17184994 (or 17184984 counting only the distinct ones).

The product of its (nonzero) digits is 196608, while the sum is 44.

Adding to 81324408121280 its reverse (8212180442318), we get a palindrome (89536588563598).

The spelling of 81324408121280 in words is "eighty-one trillion, three hundred twenty-four billion, four hundred eight million, one hundred twenty-one thousand, two hundred eighty".