428042580821 has 2 divisors, whose sum is σ = 428042580822. Its totient is φ = 428042580820.

The previous prime is 428042580809. The next prime is 428042580877. The reversal of 428042580821 is 128085240824.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 427141980721 + 900600100 = 653561^2 + 30010^2 .

It is a cyclic number.

It is not a de Polignac number, because 428042580821 - 2¹⁸ = 428042318677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (428042580881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214021290410 + 214021290411.

It is an arithmetic number, because the mean of its divisors is an integer number (214021290411).

Almost surely, 2^428042580821 is an apocalyptic number.

It is an amenable number.

428042580821 is a deficient number, since it is larger than the sum of its proper divisors (1).

428042580821 is an equidigital number, since it uses as much as digits as its factorization.

428042580821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 327680, while the sum is 44.

The spelling of 428042580821 in words is "four hundred twenty-eight billion, forty-two million, five hundred eighty thousand, eight hundred twenty-one".