81342080 has 64 divisors (see below), whose sum is σ = 195993000. Its totient is φ = 32280576.

The previous prime is 81342077. The next prime is 81342083. The reversal of 81342080 is 8024318.

It is an interprime number because it is at equal distance from previous prime (81342077) and next prime (81342083).

It can be written as a sum of positive squares in 4 ways, for example, as 27290176 + 54051904 = 5224^2 + 7352^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (81342083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94934 + ... + 95786.

Almost surely, 2^81342080 is an apocalyptic number.

81342080 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81342080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97996500).

81342080 is an abundant number, since it is smaller than the sum of its proper divisors (114650920).

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

81342080 is a wasteful number, since it uses less digits than its factorization.

81342080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021 (or 1009 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 81342080 is about 9018.9844217628. The cubic root of 81342080 is about 433.2831079198.

Adding to 81342080 its reverse (8024318), we get a palindrome (89366398).

The spelling of 81342080 in words is "eighty-one million, three hundred forty-two thousand, eighty".