81145332 has 72 divisors (see below), whose sum is σ = 212284800. Its totient is φ = 26120640.

The previous prime is 81145327. The next prime is 81145349. The reversal of 81145332 is 23354118.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 81145296 and 81145305.

It is a congruent number.

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, 135169 + ... + 135767.

It is an arithmetic number, because the mean of its divisors is an integer number (2948400).

Almost surely, 2^81145332 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 81145332, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106142400).

81145332 is an abundant number, since it is smaller than the sum of its proper divisors (131139468).

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

81145332 is a wasteful number, since it uses less digits than its factorization.

81145332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733 (or 728 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 81145332 is about 9008.0703816078. The cubic root of 81145332 is about 432.9334881046.

The spelling of 81145332 in words is "eighty-one million, one hundred forty-five thousand, three hundred thirty-two".