81108680 has 32 divisors (see below), whose sum is σ = 182763000. Its totient is φ = 32395776.

The previous prime is 81108667. The next prime is 81108697. The reversal of 81108680 is 8680118.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 79673476 + 1435204 = 8926^2 + 1198^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40994 + ... + 42926.

Almost surely, 2^81108680 is an apocalyptic number.

It is an amenable number.

81108680 is an abundant number, since it is smaller than the sum of its proper divisors (101654320).

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

81108680 is a wasteful number, since it uses less digits than its factorization.

81108680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2993 (or 2989 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 32.

The square root of 81108680 is about 9006.0357538708. The cubic root of 81108680 is about 432.8682953305.

Adding to 81108680 its reverse (8680118), we get a palindrome (89788798).

The spelling of 81108680 in words is "eighty-one million, one hundred eight thousand, six hundred eighty".