820576621 has 8 divisors (see below), whose sum is σ = 877450104. Its totient is φ = 764659200.

The previous prime is 820576609. The next prime is 820576649. The reversal of 820576621 is 126675028.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 327248100 + 493328521 = 18090^2 + 22211^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 820576621 - 2¹³ = 820568429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820576021) 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 7 ways as a sum of consecutive naturals, for example, 237240 + ... + 240673.

It is an arithmetic number, because the mean of its divisors is an integer number (109681263).

Almost surely, 2^820576621 is an apocalyptic number.

It is an amenable number.

820576621 is a deficient number, since it is larger than the sum of its proper divisors (56873483).

820576621 is a wasteful number, since it uses less digits than its factorization.

820576621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 478031.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 820576621 is about 28645.7085965769. The cubic root of 820576621 is about 936.2095058609.

The spelling of 820576621 in words is "eight hundred twenty million, five hundred seventy-six thousand, six hundred twenty-one".