81319324472 has 16 divisors (see below), whose sum is σ = 152478175200. Its totient is φ = 40658477760.

The previous prime is 81319324433. The next prime is 81319324553. The reversal of 81319324472 is 27442391318.

It is a super-2 number, since 2×81319324472² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188804 + ... + 445292.

It is an arithmetic number, because the mean of its divisors is an integer number (9529885950).

Almost surely, 2^81319324472 is an apocalyptic number.

It is an amenable number.

81319324472 is a deficient number, since it is larger than the sum of its proper divisors (71158850728).

81319324472 is a wasteful number, since it uses less digits than its factorization.

81319324472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296126 (or 296122 counting only the distinct ones).

The product of its digits is 290304, while the sum is 44.

The spelling of 81319324472 in words is "eighty-one billion, three hundred nineteen million, three hundred twenty-four thousand, four hundred seventy-two".