820321513 has 8 divisors (see below), whose sum is σ = 907155936. Its totient is φ = 735530400.

The previous prime is 820321493. The next prime is 820321517. The reversal of 820321513 is 315123028.

820321513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-820321513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820321517) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 509983 + ... + 511588.

It is an arithmetic number, because the mean of its divisors is an integer number (113394492).

Almost surely, 2^820321513 is an apocalyptic number.

It is an amenable number.

820321513 is a deficient number, since it is larger than the sum of its proper divisors (86834423).

820321513 is a wasteful number, since it uses less digits than its factorization.

820321513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021655.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 820321513 is about 28641.2554368694. The cubic root of 820321513 is about 936.1124768193.

The spelling of 820321513 in words is "eight hundred twenty million, three hundred twenty-one thousand, five hundred thirteen".