675565821 has 48 divisors (see below), whose sum is σ = 1172920320. Its totient is φ = 366331680.

The previous prime is 675565783. The next prime is 675565823. The reversal of 675565821 is 128565576.

675565821 is a `hidden beast` number, since 6 + 7 + 5 + 565 + 82 + 1 = 666.

It is not a de Polignac number, because 675565821 - 2⁹ = 675565309 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (675565823) 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 47 ways as a sum of consecutive naturals, for example, 188040 + ... + 191598.

It is an arithmetic number, because the mean of its divisors is an integer number (24435840).

Almost surely, 2^675565821 is an apocalyptic number.

It is an amenable number.

675565821 is a deficient number, since it is larger than the sum of its proper divisors (497354499).

675565821 is a wasteful number, since it uses less digits than its factorization.

675565821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3726 (or 3723 counting only the distinct ones).

The product of its digits is 504000, while the sum is 45.

The square root of 675565821 is about 25991.6490627278. The cubic root of 675565821 is about 877.4503597701.

The spelling of 675565821 in words is "six hundred seventy-five million, five hundred sixty-five thousand, eight hundred twenty-one".