81384525125 has 32 divisors (see below), whose sum is σ = 104362836864. Its totient is φ = 63328608000.

The previous prime is 81384525067. The next prime is 81384525151. The reversal of 81384525125 is 52152548318.

It is not a de Polignac number, because 81384525125 - 2¹⁰ = 81384524101 is a prime.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1263962 + ... + 1326788.

It is an arithmetic number, because the mean of its divisors is an integer number (3261338652).

Almost surely, 2^81384525125 is an apocalyptic number.

It is an amenable number.

81384525125 is a deficient number, since it is larger than the sum of its proper divisors (22978311739).

81384525125 is a wasteful number, since it uses less digits than its factorization.

81384525125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63126 (or 63116 counting only the distinct ones).

The product of its digits is 384000, while the sum is 44.

The spelling of 81384525125 in words is "eighty-one billion, three hundred eighty-four million, five hundred twenty-five thousand, one hundred twenty-five".