19680561 has 24 divisors (see below), whose sum is σ = 30363840. Its totient is φ = 12247200.

The previous prime is 19680547. The next prime is 19680587. The reversal of 19680561 is 16508691.

19680561 is a `hidden beast` number, since 1 + 96 + 8 + 0 + 561 = 666.

It is not a de Polignac number, because 19680561 - 2⁹ = 19680049 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19680511) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 11331 + ... + 12951.

It is an arithmetic number, because the mean of its divisors is an integer number (1265160).

Almost surely, 2^19680561 is an apocalyptic number.

It is an amenable number.

19680561 is a deficient number, since it is larger than the sum of its proper divisors (10683279).

19680561 is a wasteful number, since it uses less digits than its factorization.

19680561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1717 (or 1714 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 19680561 is about 4436.2778316963. The cubic root of 19680561 is about 269.9888472760.

The spelling of 19680561 in words is "nineteen million, six hundred eighty thousand, five hundred sixty-one".