821022001 has 2 divisors, whose sum is σ = 821022002. Its totient is φ = 821022000.

The previous prime is 821021983. The next prime is 821022019. The reversal of 821022001 is 100220128.

It is a balanced prime because it is at equal distance from previous prime (821021983) and next prime (821022019).

It can be written as a sum of positive squares in only one way, i.e., 685182976 + 135839025 = 26176^2 + 11655^2 .

It is a cyclic number.

It is not a de Polignac number, because 821022001 - 2⁵ = 821021969 is a prime.

It is a super-2 number, since 2×821022001² = 1348154252252088002, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (821002001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410511000 + 410511001.

It is an arithmetic number, because the mean of its divisors is an integer number (410511001).

Almost surely, 2^821022001 is an apocalyptic number.

It is an amenable number.

821022001 is a deficient number, since it is larger than the sum of its proper divisors (1).

821022001 is an equidigital number, since it uses as much as digits as its factorization.

821022001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 821022001 is about 28653.4814813139. The cubic root of 821022001 is about 936.3788557071.

Adding to 821022001 its reverse (100220128), we get a palindrome (921242129).

The spelling of 821022001 in words is "eight hundred twenty-one million, twenty-two thousand, one".