81010558525 has 24 divisors (see below), whose sum is σ = 108289846784. Its totient is φ = 59762577600.

The previous prime is 81010558493. The next prime is 81010558537. The reversal of 81010558525 is 52585501018.

It is not a de Polignac number, because 81010558525 - 2⁵ = 81010558493 is a prime.

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 23 ways as a sum of consecutive naturals, for example, 196312 + ... + 447838.

Almost surely, 2^81010558525 is an apocalyptic number.

It is an amenable number.

81010558525 is a deficient number, since it is larger than the sum of its proper divisors (27279288259).

81010558525 is a wasteful number, since it uses less digits than its factorization.

81010558525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252541 (or 252536 counting only the distinct ones).

The product of its (nonzero) digits is 80000, while the sum is 40.

The spelling of 81010558525 in words is "eighty-one billion, ten million, five hundred fifty-eight thousand, five hundred twenty-five".