81244080 has 160 divisors (see below), whose sum is σ = 289713600. Its totient is φ = 20901888.

The previous prime is 81244069. The next prime is 81244099. The reversal of 81244080 is 8044218.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61992 + ... + 63288.

It is an arithmetic number, because the mean of its divisors is an integer number (1810710).

Almost surely, 2^81244080 is an apocalyptic number.

81244080 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 81244080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144856800).

81244080 is an abundant number, since it is smaller than the sum of its proper divisors (208469520).

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

81244080 is a wasteful number, since it uses less digits than its factorization.

81244080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1348 (or 1336 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 81244080 is about 9013.5498001620. The cubic root of 81244080 is about 433.1090331626.

Adding to 81244080 its reverse (8044218), we get a palindrome (89288298).

The spelling of 81244080 in words is "eighty-one million, two hundred forty-four thousand, eighty".