6442530021 has 16 divisors (see below), whose sum is σ = 9802449600. Its totient is φ = 4178937744.

The previous prime is 6442529981. The next prime is 6442530049. The reversal of 6442530021 is 1200352446.

It is not a de Polignac number, because 6442530021 - 2¹⁰ = 6442528997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6442530071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3223491 + ... + 3225488.

It is an arithmetic number, because the mean of its divisors is an integer number (612653100).

Almost surely, 2^6442530021 is an apocalyptic number.

It is an amenable number.

6442530021 is a deficient number, since it is larger than the sum of its proper divisors (3359919579).

6442530021 is a wasteful number, since it uses less digits than its factorization.

6442530021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6449025 (or 6449019 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 6442530021 is about 80265.3724902588. The cubic root of 6442530021 is about 1860.7391001286.

Adding to 6442530021 its reverse (1200352446), we get a palindrome (7642882467).

The spelling of 6442530021 in words is "six billion, four hundred forty-two million, five hundred thirty thousand, twenty-one".