81589637292 has 12 divisors (see below), whose sum is σ = 190375820376. Its totient is φ = 27196545760.

The previous prime is 81589637287. The next prime is 81589637317. The reversal of 81589637292 is 29273698518.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3399568209 + ... + 3399568232.

It is an arithmetic number, because the mean of its divisors is an integer number (15864651698).

Almost surely, 2^81589637292 is an apocalyptic number.

It is an amenable number.

81589637292 is an abundant number, since it is smaller than the sum of its proper divisors (108786183084).

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

81589637292 is a wasteful number, since it uses less digits than its factorization.

81589637292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6799136448 (or 6799136446 counting only the distinct ones).

The product of its digits is 13063680, while the sum is 60.

The spelling of 81589637292 in words is "eighty-one billion, five hundred eighty-nine million, six hundred thirty-seven thousand, two hundred ninety-two".