4785171821 has 2 divisors, whose sum is σ = 4785171822. Its totient is φ = 4785171820.

The previous prime is 4785171817. The next prime is 4785171829. The reversal of 4785171821 is 1281715874.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2909415721 + 1875756100 = 53939^2 + 43310^2 .

It is a cyclic number.

It is not a de Polignac number, because 4785171821 - 2² = 4785171817 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4785171829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2392585910 + 2392585911.

It is an arithmetic number, because the mean of its divisors is an integer number (2392585911).

Almost surely, 2^4785171821 is an apocalyptic number.

It is an amenable number.

4785171821 is a deficient number, since it is larger than the sum of its proper divisors (1).

4785171821 is an equidigital number, since it uses as much as digits as its factorization.

4785171821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 125440, while the sum is 44.

The square root of 4785171821 is about 69174.9363642642. The cubic root of 4785171821 is about 1685.1265151684.

The spelling of 4785171821 in words is "four billion, seven hundred eighty-five million, one hundred seventy-one thousand, eight hundred twenty-one".