820942559 has 4 divisors (see below), whose sum is σ = 823423080. Its totient is φ = 818462040.

The previous prime is 820942543. The next prime is 820942567. The reversal of 820942559 is 955249028.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 820942559 - 2⁴ = 820942543 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 (820962559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1239764 + ... + 1240425.

It is an arithmetic number, because the mean of its divisors is an integer number (205855770).

Almost surely, 2^820942559 is an apocalyptic number.

820942559 is a deficient number, since it is larger than the sum of its proper divisors (2480521).

820942559 is a wasteful number, since it uses less digits than its factorization.

820942559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2480520.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 820942559 is about 28652.0951938946. The cubic root of 820942559 is about 936.3486534274.

The spelling of 820942559 in words is "eight hundred twenty million, nine hundred forty-two thousand, five hundred fifty-nine".