428420989021 has 2 divisors, whose sum is σ = 428420989022. Its totient is φ = 428420989020.

The previous prime is 428420988967. The next prime is 428420989049. The reversal of 428420989021 is 120989024824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 253224329796 + 175196659225 = 503214^2 + 418565^2 .

It is a cyclic number.

It is not a de Polignac number, because 428420989021 - 2⁷ = 428420988893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (428420980021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214210494510 + 214210494511.

It is an arithmetic number, because the mean of its divisors is an integer number (214210494511).

Almost surely, 2^428420989021 is an apocalyptic number.

It is an amenable number.

428420989021 is a deficient number, since it is larger than the sum of its proper divisors (1).

428420989021 is an equidigital number, since it uses as much as digits as its factorization.

428420989021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 663552, while the sum is 49.

The spelling of 428420989021 in words is "four hundred twenty-eight billion, four hundred twenty million, nine hundred eighty-nine thousand, twenty-one".