4189764591821 has 2 divisors, whose sum is σ = 4189764591822. Its totient is φ = 4189764591820.

The previous prime is 4189764591811. The next prime is 4189764591833. The reversal of 4189764591821 is 1281954679814.

4189764591821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3900012774025 + 289751817796 = 1974845^2 + 538286^2 .

It is a cyclic number.

It is not a de Polignac number, because 4189764591821 - 2¹⁸ = 4189764329677 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4189764591811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2094882295910 + 2094882295911.

It is an arithmetic number, because the mean of its divisors is an integer number (2094882295911).

Almost surely, 2^{4189764591821} is an apocalyptic number.

It is an amenable number.

4189764591821 is a deficient number, since it is larger than the sum of its proper divisors (1).

4189764591821 is an equidigital number, since it uses as much as digits as its factorization.

4189764591821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34836480, while the sum is 65.

The spelling of 4189764591821 in words is "four trillion, one hundred eighty-nine billion, seven hundred sixty-four million, five hundred ninety-one thousand, eight hundred twenty-one".