81552072 has 96 divisors (see below), whose sum is σ = 244926720. Its totient is φ = 22538880.

The previous prime is 81552061. The next prime is 81552073. The reversal of 81552072 is 27025518.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (81552073) 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, 35338 + ... + 37574.

It is an arithmetic number, because the mean of its divisors is an integer number (2551320).

Almost surely, 2^81552072 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 81552072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122463360).

81552072 is an abundant number, since it is smaller than the sum of its proper divisors (163374648).

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

81552072 is a wasteful number, since it uses less digits than its factorization.

81552072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2291 (or 2280 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 81552072 is about 9030.6185834637. The cubic root of 81552072 is about 433.6556408175.

The spelling of 81552072 in words is "eighty-one million, five hundred fifty-two thousand, seventy-two".