81875072 has 32 divisors (see below), whose sum is σ = 165562320. Its totient is φ = 40322304.

The previous prime is 81875071. The next prime is 81875083. The reversal of 81875072 is 27057818.

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (81875071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3803 + ... + 13349.

Almost surely, 2^81875072 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 81875072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82781160).

81875072 is an abundant number, since it is smaller than the sum of its proper divisors (83687248).

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

81875072 is an equidigital number, since it uses as much as digits as its factorization.

81875072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9628 (or 9616 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 81875072 is about 9048.4845139946. The cubic root of 81875072 is about 434.2274074208.

The spelling of 81875072 in words is "eighty-one million, eight hundred seventy-five thousand, seventy-two".