80105661 has 12 divisors (see below), whose sum is σ = 115792092. Its totient is φ = 53365056.

The previous prime is 80105617. The next prime is 80105671. The reversal of 80105661 is 16650108.

It can be written as a sum of positive squares in 2 ways, for example, as 23765625 + 56340036 = 4875^2 + 7506^2 .

It is not a de Polignac number, because 80105661 - 2⁷ = 80105533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80105611) 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 11 ways as a sum of consecutive naturals, for example, 15745 + ... + 20201.

It is an arithmetic number, because the mean of its divisors is an integer number (9649341).

Almost surely, 2^80105661 is an apocalyptic number.

It is an amenable number.

80105661 is a deficient number, since it is larger than the sum of its proper divisors (35686431).

80105661 is a wasteful number, since it uses less digits than its factorization.

80105661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6460 (or 6457 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 80105661 is about 8950.1765904366. The cubic root of 80105661 is about 431.0765543213.

Adding to 80105661 its reverse (16650108), we get a palindrome (96755769).

The spelling of 80105661 in words is "eighty million, one hundred five thousand, six hundred sixty-one".