81529563385 has 16 divisors (see below), whose sum is σ = 99766389312. Its totient is φ = 63945604800.

The previous prime is 81529563343. The next prime is 81529563463. The reversal of 81529563385 is 58336592518.

It is not a de Polignac number, because 81529563385 - 2⁷ = 81529563257 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 506026 + ... + 647395.

It is an arithmetic number, because the mean of its divisors is an integer number (6235399332).

Almost surely, 2^81529563385 is an apocalyptic number.

It is an amenable number.

81529563385 is a deficient number, since it is larger than the sum of its proper divisors (18236825927).

81529563385 is a wasteful number, since it uses less digits than its factorization.

81529563385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1153704.

The product of its digits is 7776000, while the sum is 55.

The spelling of 81529563385 in words is "eighty-one billion, five hundred twenty-nine million, five hundred sixty-three thousand, three hundred eighty-five".