6424244221 has 6 divisors (see below), whose sum is σ = 6465448410. Its totient is φ = 6383300976.

The previous prime is 6424244201. The next prime is 6424244231. The reversal of 6424244221 is 1224424246.

It can be written as a sum of positive squares in 3 ways, for example, as 1625218596 + 4799025625 = 40314^2 + 69275^2 .

It is not a de Polignac number, because 6424244221 - 2⁷ = 6424244093 is a prime.

It is a super-2 number, since 2×6424244221² = 82541827622103793682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6424244201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105666 + ... + 154963.

It is an arithmetic number, because the mean of its divisors is an integer number (1077574735).

Almost surely, 2^6424244221 is an apocalyptic number.

It is an amenable number.

6424244221 is a deficient number, since it is larger than the sum of its proper divisors (41204189).

6424244221 is an equidigital number, since it uses as much as digits as its factorization.

6424244221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260943 (or 260786 counting only the distinct ones).

The product of its digits is 24576, while the sum is 31.

The square root of 6424244221 is about 80151.3831508852. The cubic root of 6424244221 is about 1858.9769898565.

Adding to 6424244221 its reverse (1224424246), we get a palindrome (7648668467).

The spelling of 6424244221 in words is "six billion, four hundred twenty-four million, two hundred forty-four thousand, two hundred twenty-one".