820343961 has 6 divisors (see below), whose sum is σ = 1184941290. Its totient is φ = 546895968.

The previous prime is 820343941. The next prime is 820343971. The reversal of 820343961 is 169343028.

820343961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 804062736 + 16281225 = 28356^2 + 4035^2 .

It is not a de Polignac number, because 820343961 - 2¹⁸ = 820081817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (820343941) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45574656 + ... + 45574673.

It is an arithmetic number, because the mean of its divisors is an integer number (197490215).

Almost surely, 2^820343961 is an apocalyptic number.

It is an amenable number.

820343961 is a deficient number, since it is larger than the sum of its proper divisors (364597329).

820343961 is a wasteful number, since it uses less digits than its factorization.

820343961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91149335 (or 91149332 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 820343961 is about 28641.6473164516. The cubic root of 820343961 is about 936.1210156100.

Adding to 820343961 its reverse (169343028), we get a palindrome (989686989).

The spelling of 820343961 in words is "eight hundred twenty million, three hundred forty-three thousand, nine hundred sixty-one".