81552128 has 72 divisors (see below), whose sum is σ = 197057952. Its totient is φ = 32882688.

The previous prime is 81552113. The next prime is 81552131. The reversal of 81552128 is 82125518.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 81552094 and 81552103.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29126 + ... + 31802.

It is an arithmetic number, because the mean of its divisors is an integer number (2736916).

Almost surely, 2^81552128 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 81552128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98528976).

81552128 is an abundant number, since it is smaller than the sum of its proper divisors (115505824).

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

81552128 is a wasteful number, since it uses less digits than its factorization.

81552128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2717 (or 2703 counting only the distinct ones).

The product of its digits is 6400, while the sum is 32.

The square root of 81552128 is about 9030.6216840260. The cubic root of 81552128 is about 433.6557400780.

The spelling of 81552128 in words is "eighty-one million, five hundred fifty-two thousand, one hundred twenty-eight".