81534686524 has 24 divisors (see below), whose sum is σ = 144701524800. Its totient is φ = 40194772800.

The previous prime is 81534686503. The next prime is 81534686537. The reversal of 81534686524 is 42568643518.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 325659 + ... + 518770.

It is an arithmetic number, because the mean of its divisors is an integer number (6029230200).

Almost surely, 2^81534686524 is an apocalyptic number.

It is an amenable number.

81534686524 is a deficient number, since it is larger than the sum of its proper divisors (63166838276).

81534686524 is a wasteful number, since it uses less digits than its factorization.

81534686524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844773 (or 844771 counting only the distinct ones).

The product of its digits is 5529600, while the sum is 52.

The spelling of 81534686524 in words is "eighty-one billion, five hundred thirty-four million, six hundred eighty-six thousand, five hundred twenty-four".