81110660 has 24 divisors (see below), whose sum is σ = 174937560. Its totient is φ = 31567104.

The previous prime is 81110657. The next prime is 81110681. The reversal of 81110660 is 6601118.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 42198016 + 38912644 = 6496^2 + 6238^2 .

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, 54065 + ... + 55544.

It is an arithmetic number, because the mean of its divisors is an integer number (7289065).

Almost surely, 2^81110660 is an apocalyptic number.

It is an amenable number.

81110660 is an abundant number, since it is smaller than the sum of its proper divisors (93826900).

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

81110660 is a wasteful number, since it uses less digits than its factorization.

81110660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109655 (or 109653 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 81110660 is about 9006.1456794791. The cubic root of 81110660 is about 432.8718176508.

Adding to 81110660 its reverse (6601118), we get a palindrome (87711778).

The spelling of 81110660 in words is "eighty-one million, one hundred ten thousand, six hundred sixty".