81747301536 has 144 divisors (see below), whose sum is σ = 243833151744. Its totient is φ = 25948380672.

The previous prime is 81747301529. The next prime is 81747301541. The reversal of 81747301536 is 63510374718.

81747301536 is a `hidden beast` number, since 81 + 7 + 4 + 7 + 30 + 1 + 536 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a junction number, because it is equal to n+sod(n) for n = 81747301491 and 81747301500.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 419221 + ... + 582443.

It is an arithmetic number, because the mean of its divisors is an integer number (1693285776).

Almost surely, 2^81747301536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81747301536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121916575872).

81747301536 is an abundant number, since it is smaller than the sum of its proper divisors (162085850208).

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

81747301536 is a wasteful number, since it uses less digits than its factorization.

81747301536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163323 (or 163312 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The spelling of 81747301536 in words is "eighty-one billion, seven hundred forty-seven million, three hundred one thousand, five hundred thirty-six".