6520066021 has 8 divisors (see below), whose sum is σ = 7457480000. Its totient is φ = 5584146048.

The previous prime is 6520066019. The next prime is 6520066067. The reversal of 6520066021 is 1206600256.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6520066021 - 2¹ = 6520066019 is a prime.

It is a super-2 number, since 2×6520066021² = 85022521836397544882, 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 (6520066001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364131 + ... + 381616.

It is an arithmetic number, because the mean of its divisors is an integer number (932185000).

Almost surely, 2^6520066021 is an apocalyptic number.

It is an amenable number.

6520066021 is a deficient number, since it is larger than the sum of its proper divisors (937413979).

6520066021 is a wasteful number, since it uses less digits than its factorization.

6520066021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747003.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 6520066021 is about 80746.9257681059. The cubic root of 6520066021 is about 1868.1740324730.

Adding to 6520066021 its reverse (1206600256), we get a palindrome (7726666277).

The spelling of 6520066021 in words is "six billion, five hundred twenty million, sixty-six thousand, twenty-one".