8551020521 has 2 divisors, whose sum is σ = 8551020522. Its totient is φ = 8551020520.

The previous prime is 8551020503. The next prime is 8551020571. The reversal of 8551020521 is 1250201558.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4408296025 + 4142724496 = 66395^2 + 64364^2 .

It is a cyclic number.

It is not a de Polignac number, because 8551020521 - 2¹⁰ = 8551019497 is a prime.

It is a super-2 number, since 2×8551020521² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (8551020571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4275510260 + 4275510261.

It is an arithmetic number, because the mean of its divisors is an integer number (4275510261).

Almost surely, 2^8551020521 is an apocalyptic number.

It is an amenable number.

8551020521 is a deficient number, since it is larger than the sum of its proper divisors (1).

8551020521 is an equidigital number, since it uses as much as digits as its factorization.

8551020521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4000, while the sum is 29.

The square root of 8551020521 is about 92471.7282254420. The cubic root of 8551020521 is about 2044.9027056610.

The spelling of 8551020521 in words is "eight billion, five hundred fifty-one million, twenty thousand, five hundred twenty-one".