6435652021 has 2 divisors, whose sum is σ = 6435652022. Its totient is φ = 6435652020.

The previous prime is 6435652019. The next prime is 6435652037. The reversal of 6435652021 is 1202565346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5462835921 + 972816100 = 73911^2 + 31190^2 .

It is a cyclic number.

It is not a de Polignac number, because 6435652021 - 2¹ = 6435652019 is a prime.

Together with 6435652019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6435652721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3217826010 + 3217826011.

It is an arithmetic number, because the mean of its divisors is an integer number (3217826011).

Almost surely, 2^6435652021 is an apocalyptic number.

It is an amenable number.

6435652021 is a deficient number, since it is larger than the sum of its proper divisors (1).

6435652021 is an equidigital number, since it uses as much as digits as its factorization.

6435652021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 34.

The square root of 6435652021 is about 80222.5156735938. The cubic root of 6435652021 is about 1860.0766936619.

The spelling of 6435652021 in words is "six billion, four hundred thirty-five million, six hundred fifty-two thousand, twenty-one".