8521045021 has 2 divisors, whose sum is σ = 8521045022. Its totient is φ = 8521045020.

The previous prime is 8521044979. The next prime is 8521045067. The reversal of 8521045021 is 1205401258.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5128564996 + 3392480025 = 71614^2 + 58245^2 .

It is a cyclic number.

It is not a de Polignac number, because 8521045021 - 2¹³ = 8521036829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8521045081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4260522510 + 4260522511.

It is an arithmetic number, because the mean of its divisors is an integer number (4260522511).

Almost surely, 2^8521045021 is an apocalyptic number.

It is an amenable number.

8521045021 is a deficient number, since it is larger than the sum of its proper divisors (1).

8521045021 is an equidigital number, since it uses as much as digits as its factorization.

8521045021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3200, while the sum is 28.

The square root of 8521045021 is about 92309.5066664317. The cubic root of 8521045021 is about 2042.5104474895.

Adding to 8521045021 its reverse (1205401258), we get a palindrome (9726446279).

The spelling of 8521045021 in words is "eight billion, five hundred twenty-one million, forty-five thousand, twenty-one".