81275603520000 has 800 divisors, whose sum is σ = 277800432205824. Its totient is φ = 21099059200000.

The previous prime is 81275603519959. The next prime is 81275603520049. The reversal of 81275603520000 is 2530657218.

It is a tau number, because it is divible by the number of its divisors (800).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8617915285 + ... + 8617924715.

Almost surely, 2^{81275603520000} is an apocalyptic number.

81275603520000 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 81275603520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138900216102912).

81275603520000 is an abundant number, since it is smaller than the sum of its proper divisors (196524828685824).

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

81275603520000 is an equidigital number, since it uses as much as digits as its factorization.

81275603520000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9710 (or 9679 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 39.

The spelling of 81275603520000 in words is "eighty-one trillion, two hundred seventy-five billion, six hundred three million, five hundred twenty thousand".