81478172160 has 1320 divisors, whose sum is σ = 371864174616. Its totient is φ = 16930529280.

The previous prime is 81478172143. The next prime is 81478172183. The reversal of 81478172160 is 6127187418.

81478172160 is a `hidden beast` number, since 8 + 1 + 478 + 17 + 2 + 160 = 666.

It is a tau number, because it is divible by the number of its divisors (1320).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 131 ways as a sum of consecutive naturals, for example, 7407106555 + ... + 7407106565.

Almost surely, 2^81478172160 is an apocalyptic number.

81478172160 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 81478172160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185932087308).

81478172160 is an abundant number, since it is smaller than the sum of its proper divisors (290386002456).

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

81478172160 is an frugal number, since it uses more digits than its factorization.

81478172160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 45.

The spelling of 81478172160 in words is "eighty-one billion, four hundred seventy-eight million, one hundred seventy-two thousand, one hundred sixty".