820217605 has 8 divisors (see below), whose sum is σ = 1027055232. Its totient is φ = 627644688.

The previous prime is 820217597. The next prime is 820217627. The reversal of 820217605 is 506712028.

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 820217605 - 2³ = 820217597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 3566049 + ... + 3566278.

It is an arithmetic number, because the mean of its divisors is an integer number (128381904).

Almost surely, 2^820217605 is an apocalyptic number.

It is an amenable number.

820217605 is a deficient number, since it is larger than the sum of its proper divisors (206837627).

820217605 is a wasteful number, since it uses less digits than its factorization.

820217605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7132355.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 820217605 is about 28639.4414226255. The cubic root of 820217605 is about 936.0729501699.

The spelling of 820217605 in words is "eight hundred twenty million, two hundred seventeen thousand, six hundred five".