820455673 has 4 divisors (see below), whose sum is σ = 833905828. Its totient is φ = 807005520.

The previous prime is 820455619. The next prime is 820455679. The reversal of 820455673 is 376554028.

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

It can be written as a sum of positive squares in 2 ways, for example, as 308248249 + 512207424 = 17557^2 + 22632^2 .

It is a cyclic number.

It is not a de Polignac number, because 820455673 - 2⁹ = 820455161 is a prime.

It is a super-2 number, since 2×820455673² = 1346295022715765858, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820455679) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6724986 + ... + 6725107.

It is an arithmetic number, because the mean of its divisors is an integer number (208476457).

Almost surely, 2^820455673 is an apocalyptic number.

It is an amenable number.

820455673 is a deficient number, since it is larger than the sum of its proper divisors (13450155).

820455673 is a wasteful number, since it uses less digits than its factorization.

820455673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13450154.

The product of its (nonzero) digits is 201600, while the sum is 40.

The square root of 820455673 is about 28643.5974172240. The cubic root of 820455673 is about 936.1635064063.

It can be divided in two parts, 820455 and 673, that added together give a palindrome (821128).

The spelling of 820455673 in words is "eight hundred twenty million, four hundred fifty-five thousand, six hundred seventy-three".