81347136 has 168 divisors, whose sum is σ = 245424960. Its totient is φ = 23721984.

The previous prime is 81347129. The next prime is 81347137. The reversal of 81347136 is 63174318.

It is a junction number, because it is equal to n+sod(n) for n = 81347097 and 81347106.

It is not an unprimeable number, because it can be changed into a prime (81347137) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 746250 + ... + 746358.

Almost surely, 2^81347136 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 81347136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122712480).

81347136 is an abundant number, since it is smaller than the sum of its proper divisors (164077824).

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

81347136 is a wasteful number, since it uses less digits than its factorization.

81347136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 150 counting only the distinct ones).

The product of its digits is 12096, while the sum is 33.

The square root of 81347136 is about 9019.2647150419. The cubic root of 81347136 is about 433.2920849626.

The spelling of 81347136 in words is "eighty-one million, three hundred forty-seven thousand, one hundred thirty-six".