81377395200 has 1200 divisors, whose sum is σ = 337066060320. Its totient is φ = 19349176320.

The previous prime is 81377395189. The next prime is 81377395207. The reversal of 81377395200 is 259377318.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1200).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (81377395207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 4283020791 + ... + 4283020809.

Almost surely, 2^81377395200 is an apocalyptic number.

81377395200 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 81377395200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168533030160).

81377395200 is an abundant number, since it is smaller than the sum of its proper divisors (255688665120).

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

81377395200 is an frugal number, since it uses more digits than its factorization.

81377395200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The spelling of 81377395200 in words is "eighty-one billion, three hundred seventy-seven million, three hundred ninety-five thousand, two hundred".