81119742 has 32 divisors (see below), whose sum is σ = 178827264. Its totient is φ = 24326400.

The previous prime is 81119741. The next prime is 81119743. The reversal of 81119742 is 24791118.

It is an interprime number because it is at equal distance from previous prime (81119741) and next prime (81119743).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81119741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67 + ... + 12737.

It is an arithmetic number, because the mean of its divisors is an integer number (5588352).

Almost surely, 2^81119742 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81119742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89413632).

81119742 is an abundant number, since it is smaller than the sum of its proper divisors (97707522).

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

81119742 is a wasteful number, since it uses less digits than its factorization.

81119742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12784.

The product of its digits is 4032, while the sum is 33.

The square root of 81119742 is about 9006.6498766189. The cubic root of 81119742 is about 432.8879733371.

The spelling of 81119742 in words is "eighty-one million, one hundred nineteen thousand, seven hundred forty-two".