81065436 has 48 divisors (see below), whose sum is σ = 192864000. Its totient is φ = 26497152.

The previous prime is 81065417. The next prime is 81065437. The reversal of 81065436 is 63456018.

It is a junction number, because it is equal to n+sod(n) for n = 81065397 and 81065406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81065437) 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, 198000 + ... + 198408.

It is an arithmetic number, because the mean of its divisors is an integer number (4018000).

Almost surely, 2^81065436 is an apocalyptic number.

It is an amenable number.

81065436 is an abundant number, since it is smaller than the sum of its proper divisors (111798564).

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

81065436 is a wasteful number, since it uses less digits than its factorization.

81065436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698 (or 696 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 81065436 is about 9003.6345994271. The cubic root of 81065436 is about 432.7913521300.

The spelling of 81065436 in words is "eighty-one million, sixty-five thousand, four hundred thirty-six".