81061552 has 80 divisors (see below), whose sum is σ = 187488000. Its totient is φ = 33465600.

The previous prime is 81061549. The next prime is 81061553. The reversal of 81061552 is 25516018.

It is a self number, because there is not a number n which added to its sum of digits gives 81061552.

It is not an unprimeable number, because it can be changed into a prime (81061553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 162199 + ... + 162697.

It is an arithmetic number, because the mean of its divisors is an integer number (2343600).

Almost surely, 2^81061552 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 81061552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93744000).

81061552 is an abundant number, since it is smaller than the sum of its proper divisors (106426448).

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

81061552 is a wasteful number, since it uses less digits than its factorization.

81061552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602 (or 596 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 28.

The square root of 81061552 is about 9003.4189061711. The cubic root of 81061552 is about 432.7844400659.

The spelling of 81061552 in words is "eighty-one million, sixty-one thousand, five hundred fifty-two".