8665821001 has 2 divisors, whose sum is σ = 8665821002. Its totient is φ = 8665821000.

The previous prime is 8665820987. The next prime is 8665821013. The reversal of 8665821001 is 1001285668.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4996369225 + 3669451776 = 70685^2 + 60576^2 .

It is a cyclic number.

It is not a de Polignac number, because 8665821001 - 2²⁵ = 8632266569 is a prime.

It is not a weakly prime, because it can be changed into another prime (8665821061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4332910500 + 4332910501.

It is an arithmetic number, because the mean of its divisors is an integer number (4332910501).

Almost surely, 2^8665821001 is an apocalyptic number.

It is an amenable number.

8665821001 is a deficient number, since it is larger than the sum of its proper divisors (1).

8665821001 is an equidigital number, since it uses as much as digits as its factorization.

8665821001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 8665821001 is about 93090.3915611058. The cubic root of 8665821001 is about 2054.0132368852.

The spelling of 8665821001 in words is "eight billion, six hundred sixty-five million, eight hundred twenty-one thousand, one".