81315481554824 has 128 divisors (see below), whose sum is σ = 186451645737600. Its totient is φ = 32765955747840.

The previous prime is 81315481554823. The next prime is 81315481554851. The reversal of 81315481554824 is 42845518451318.

It is a happy number.

It is a super-2 number, since 2×81315481554824² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81315481554823) 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 31 ways as a sum of consecutive naturals, for example, 3350867 + ... + 13185570.

It is an arithmetic number, because the mean of its divisors is an integer number (1456653482325).

Almost surely, 2^{81315481554824} is an apocalyptic number.

It is an amenable number.

81315481554824 is an abundant number, since it is smaller than the sum of its proper divisors (105136164182776).

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

81315481554824 is a wasteful number, since it uses less digits than its factorization.

81315481554824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16536663 (or 16536659 counting only the distinct ones).

The product of its digits is 24576000, while the sum is 59.

The spelling of 81315481554824 in words is "eighty-one trillion, three hundred fifteen billion, four hundred eighty-one million, five hundred fifty-four thousand, eight hundred twenty-four".