81226320000 has 480 divisors, whose sum is σ = 313673904720. Its totient is φ = 18563328000.

The previous prime is 81226319971. The next prime is 81226320011. The reversal of 81226320000 is 2362218.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 11756547 + ... + 11763453.

Almost surely, 2^81226320000 is an apocalyptic number.

81226320000 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 81226320000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156836952360).

81226320000 is an abundant number, since it is smaller than the sum of its proper divisors (232447584720).

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

81226320000 is an equidigital number, since it uses as much as digits as its factorization.

81226320000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6958 (or 6924 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

Adding to 81226320000 its reverse (2362218), we get a palindrome (81228682218).

The spelling of 81226320000 in words is "eighty-one billion, two hundred twenty-six million, three hundred twenty thousand".