81601160 has 16 divisors (see below), whose sum is σ = 183602700. Its totient is φ = 32640448.

The previous prime is 81601151. The next prime is 81601199. The reversal of 81601160 is 6110618.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 70324996 + 11276164 = 8386^2 + 3358^2 .

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1019975 + ... + 1020054.

Almost surely, 2^81601160 is an apocalyptic number.

It is an amenable number.

81601160 is an abundant number, since it is smaller than the sum of its proper divisors (102001540).

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

81601160 is a wasteful number, since it uses less digits than its factorization.

81601160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2040040 (or 2040036 counting only the distinct ones).

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

The square root of 81601160 is about 9033.3360393600. The cubic root of 81601160 is about 433.7426323470.

Adding to 81601160 its reverse (6110618), we get a palindrome (87711778).

The spelling of 81601160 in words is "eighty-one million, six hundred one thousand, one hundred sixty".