81315481554826 has 32 divisors (see below), whose sum is σ = 125342466480000. Its totient is φ = 39535939518912.

The previous prime is 81315481554823. The next prime is 81315481554851. The reversal of 81315481554826 is 62845518451318.

It is a super-2 number, since 2×81315481554826² (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 polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1305214225 + ... + 1305276523.

It is an arithmetic number, because the mean of its divisors is an integer number (3916952077500).

Almost surely, 2^{81315481554826} is an apocalyptic number.

81315481554826 is a deficient number, since it is larger than the sum of its proper divisors (44026984925174).

81315481554826 is a wasteful number, since it uses less digits than its factorization.

81315481554826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72286.

The product of its digits is 36864000, while the sum is 61.

The spelling of 81315481554826 in words is "eighty-one trillion, three hundred fifteen billion, four hundred eighty-one million, five hundred fifty-four thousand, eight hundred twenty-six".