81012505325 has 6 divisors (see below), whose sum is σ = 100455506634. Its totient is φ = 64810004240.

The previous prime is 81012505319. The next prime is 81012505337. The reversal of 81012505325 is 52350521018.

It can be written as a sum of positive squares in 3 ways, for example, as 20691671716 + 60320833609 = 143846^2 + 245603^2 .

It is not a de Polignac number, because 81012505325 - 2¹⁶ = 81012439789 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81012505291 and 81012505300.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1620250082 + ... + 1620250131.

It is an arithmetic number, because the mean of its divisors is an integer number (16742584439).

Almost surely, 2^81012505325 is an apocalyptic number.

It is an amenable number.

81012505325 is a deficient number, since it is larger than the sum of its proper divisors (19443001309).

81012505325 is a wasteful number, since it uses less digits than its factorization.

81012505325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3240500223 (or 3240500218 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 32.

The spelling of 81012505325 in words is "eighty-one billion, twelve million, five hundred five thousand, three hundred twenty-five".