81269798400 has 720 divisors, whose sum is σ = 343218889728. Its totient is φ = 17971200000.

The previous prime is 81269798303. The next prime is 81269798413. The reversal of 81269798400 is 489796218.

It is a tau number, because it is divible by the number of its divisors (720).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 24996775 + ... + 25000025.

Almost surely, 2^81269798400 is an apocalyptic number.

81269798400 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 81269798400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171609444864).

81269798400 is an abundant number, since it is smaller than the sum of its proper divisors (261949091328).

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

81269798400 is a wasteful number, since it uses less digits than its factorization.

81269798400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3323 (or 3299 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 81269798400 in words is "eighty-one billion, two hundred sixty-nine million, seven hundred ninety-eight thousand, four hundred".