820840753 has 2 divisors, whose sum is σ = 820840754. Its totient is φ = 820840752.

The previous prime is 820840729. The next prime is 820840771. The reversal of 820840753 is 357048028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 448041889 + 372798864 = 21167^2 + 19308^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820840753 is a prime.

It is a super-3 number, since 3×820840753³ (a number of 28 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (820840703) by changing a digit.

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 as a sum of consecutive naturals, namely, 410420376 + 410420377.

It is an arithmetic number, because the mean of its divisors is an integer number (410420377).

Almost surely, 2^820840753 is an apocalyptic number.

It is an amenable number.

820840753 is a deficient number, since it is larger than the sum of its proper divisors (1).

820840753 is an equidigital number, since it uses as much as digits as its factorization.

820840753 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 53760, while the sum is 37.

The square root of 820840753 is about 28650.3185497125. The cubic root of 820840753 is about 936.3099459479.

The spelling of 820840753 in words is "eight hundred twenty million, eight hundred forty thousand, seven hundred fifty-three".