81558375360 has 1344 divisors, whose sum is σ = 350251776000. Its totient is φ = 16028221440.

The previous prime is 81558375317. The next prime is 81558375373. The reversal of 81558375360 is 6357385518.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 916386196 + ... + 916386284.

It is an arithmetic number, because the mean of its divisors is an integer number (260604000).

Almost surely, 2^81558375360 is an apocalyptic number.

81558375360 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81558375360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175125888000).

81558375360 is an abundant number, since it is smaller than the sum of its proper divisors (268693400640).

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

81558375360 is a wasteful number, since it uses less digits than its factorization.

81558375360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175 (or 140 counting only the distinct ones).

The product of its (nonzero) digits is 3024000, while the sum is 51.

The spelling of 81558375360 in words is "eighty-one billion, five hundred fifty-eight million, three hundred seventy-five thousand, three hundred sixty".