81012593500 has 48 divisors (see below), whose sum is σ = 180269893440. Its totient is φ = 31793611200.

The previous prime is 81012593411. The next prime is 81012593507. The reversal of 81012593500 is 539521018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81012593507) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1502040 + ... + 1555039.

It is an arithmetic number, because the mean of its divisors is an integer number (3755622780).

Almost surely, 2^81012593500 is an apocalyptic number.

It is an amenable number.

81012593500 is an abundant number, since it is smaller than the sum of its proper divisors (99257299940).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81012593500 is a wasteful number, since it uses less digits than its factorization.

81012593500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3057151 (or 3057139 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 34.

The spelling of 81012593500 in words is "eighty-one billion, twelve million, five hundred ninety-three thousand, five hundred".