81365536 has 96 divisors (see below), whose sum is σ = 202487040. Its totient is φ = 31358976.

The previous prime is 81365527. The next prime is 81365539. The reversal of 81365536 is 63556318.

It is a super-3 number, since 3×81365536³ (a number of 25 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81365495 and 81365504.

It is not an unprimeable number, because it can be changed into a prime (81365539) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87120 + ... + 88048.

It is an arithmetic number, because the mean of its divisors is an integer number (2109240).

Almost surely, 2^81365536 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 81365536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101243520).

81365536 is an abundant number, since it is smaller than the sum of its proper divisors (121121504).

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

81365536 is a wasteful number, since it uses less digits than its factorization.

81365536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 986 (or 978 counting only the distinct ones).

The product of its digits is 64800, while the sum is 37.

The square root of 81365536 is about 9020.2846961723. The cubic root of 81365536 is about 433.3247514408.

The spelling of 81365536 in words is "eighty-one million, three hundred sixty-five thousand, five hundred thirty-six".