81586684428480 has 672 divisors, whose sum is σ = 351823879779840. Its totient is φ = 16858359152640.

The previous prime is 81586684428421. The next prime is 81586684428499. The reversal of 81586684428480 is 8482448668518.

81586684428480 is a `hidden beast` number, since 8 + 1 + 5 + 8 + 66 + 84 + 4 + 2 + 8 + 480 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×81586684428480² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 81586684428399 and 81586684428408.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 38667372 + ... + 40722708.

Almost surely, 2^{81586684428480} is an apocalyptic number.

81586684428480 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 81586684428480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175911939889920).

81586684428480 is an abundant number, since it is smaller than the sum of its proper divisors (270237195351360).

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

81586684428480 is a wasteful number, since it uses less digits than its factorization.

81586684428480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2055557 (or 2055544 counting only the distinct ones).

The product of its (nonzero) digits is 754974720, while the sum is 72.

The spelling of 81586684428480 in words is "eighty-one trillion, five hundred eighty-six billion, six hundred eighty-four million, four hundred twenty-eight thousand, four hundred eighty".