81108080 has 20 divisors (see below), whose sum is σ = 188576472. Its totient is φ = 32443200.

The previous prime is 81108077. The next prime is 81108089. The reversal of 81108080 is 8080118.

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81108089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 506846 + ... + 507005.

Almost surely, 2^81108080 is an apocalyptic number.

81108080 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81108080 is an abundant number, since it is smaller than the sum of its proper divisors (107468392).

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

81108080 is a wasteful number, since it uses less digits than its factorization.

81108080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013864 (or 1013858 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 81108080 is about 9006.0024428156. The cubic root of 81108080 is about 432.8672279494.

Adding to 81108080 its reverse (8080118), we get a palindrome (89188198).

The spelling of 81108080 in words is "eighty-one million, one hundred eight thousand, eighty".