1002002021 has 2 divisors, whose sum is σ = 1002002022. Its totient is φ = 1002002020.

The previous prime is 1002002009. The next prime is 1002002033. The reversal of 1002002021 is 1202002001.

It is a balanced prime because it is at equal distance from previous prime (1002002009) and next prime (1002002033).

It can be written as a sum of positive squares in only one way, i.e., 649689121 + 352312900 = 25489^2 + 18770^2 .

It is a cyclic number.

It is not a de Polignac number, because 1002002021 - 2¹⁰ = 1002000997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1002002041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 501001010 + 501001011.

It is an arithmetic number, because the mean of its divisors is an integer number (501001011).

Almost surely, 2^1002002021 is an apocalyptic number.

It is an amenable number.

1002002021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1002002021 is an equidigital number, since it uses as much as digits as its factorization.

1002002021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 1002002021 is about 31654.4155055815. The cubic root of 1002002021 is about 1000.6668954849. Note that the first 3 decimals are identical.

Adding to 1002002021 its reverse (1202002001), we get a palindrome (2204004022).

The spelling of 1002002021 in words is "one billion, two million, two thousand, twenty-one".