821303805 has 16 divisors (see below), whose sum is σ = 1501812864. Its totient is φ = 375453120.

The previous prime is 821303783. The next prime is 821303839. The reversal of 821303805 is 508303128.

It is a happy number.

It is not a de Polignac number, because 821303805 - 2⁹ = 821303293 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3910866 + ... + 3911075.

It is an arithmetic number, because the mean of its divisors is an integer number (93863304).

Almost surely, 2^821303805 is an apocalyptic number.

It is an amenable number.

821303805 is a deficient number, since it is larger than the sum of its proper divisors (680509059).

821303805 is a wasteful number, since it uses less digits than its factorization.

821303805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7821956.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 821303805 is about 28658.3985072439. The cubic root of 821303805 is about 936.4859763129.

The spelling of 821303805 in words is "eight hundred twenty-one million, three hundred three thousand, eight hundred five".