6442612821 has 12 divisors (see below), whose sum is σ = 9344936640. Its totient is φ = 4277102760.

The previous prime is 6442612811. The next prime is 6442612829. The reversal of 6442612821 is 1282162446.

6442612821 is a `hidden beast` number, since 644 + 2 + 6 + 1 + 2 + 8 + 2 + 1 = 666.

It is not a de Polignac number, because 6442612821 - 2¹³ = 6442604629 is a prime.

It is a super-2 number, since 2×6442612821² = 83014519922627156082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6442612829) 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 11 ways as a sum of consecutive naturals, for example, 1495435 + ... + 1499736.

It is an arithmetic number, because the mean of its divisors is an integer number (778744720).

Almost surely, 2^6442612821 is an apocalyptic number.

It is an amenable number.

6442612821 is a deficient number, since it is larger than the sum of its proper divisors (2902323819).

6442612821 is a wasteful number, since it uses less digits than its factorization.

6442612821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2995416 (or 2995413 counting only the distinct ones).

The product of its digits is 36864, while the sum is 36.

The square root of 6442612821 is about 80265.8882776488. Note that the first 3 decimals coincide. The cubic root of 6442612821 is about 1860.7470715590.

The spelling of 6442612821 in words is "six billion, four hundred forty-two million, six hundred twelve thousand, eight hundred twenty-one".