19680557 has 12 divisors (see below), whose sum is σ = 21540564. Its totient is φ = 17971200.

The previous prime is 19680547. The next prime is 19680587. The reversal of 19680557 is 75508691.

It can be written as a sum of positive squares in 6 ways, for example, as 64516 + 19616041 = 254^2 + 4429^2 .

It is not a de Polignac number, because 19680557 - 2¹⁰ = 19679533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19680527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16493 + ... + 17645.

It is an arithmetic number, because the mean of its divisors is an integer number (1795047).

Almost surely, 2^19680557 is an apocalyptic number.

It is an amenable number.

19680557 is a deficient number, since it is larger than the sum of its proper divisors (1860007).

19680557 is a wasteful number, since it uses less digits than its factorization.

19680557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280 (or 1267 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 41.

The square root of 19680557 is about 4436.2773808679. The cubic root of 19680557 is about 269.9888289845.

The spelling of 19680557 in words is "nineteen million, six hundred eighty thousand, five hundred fifty-seven".