81742752 has 144 divisors (see below), whose sum is σ = 286191360. Its totient is φ = 21551616.

The previous prime is 81742751. The next prime is 81742763. The reversal of 81742752 is 25724718.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (81742751) 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, 24649 + ... + 27767.

It is an arithmetic number, because the mean of its divisors is an integer number (1987440).

Almost surely, 2^81742752 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 81742752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143095680).

81742752 is an abundant number, since it is smaller than the sum of its proper divisors (204448608).

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

81742752 is a wasteful number, since it uses less digits than its factorization.

81742752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3155 (or 3144 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 81742752 is about 9041.1698358122. The cubic root of 81742752 is about 433.9933599896.

The spelling of 81742752 in words is "eighty-one million, seven hundred forty-two thousand, seven hundred fifty-two".